Responsible Person In relation to a workplace – the employer, if the workplace is to any extent under his control If the premises are not a workplace – the person who has control of the premises in connection with carrying on a trade or business The owner – where the person in control of the premises does not have control in connection with the carrying on of a trade or business Responsible Person Duties The responsible person must ensure that: – Where the premises are a workplace Any duty imposed is complied with (Art.8 – Art.22) – Where the premises are not a workplace Ensure that any duties imposed are complied with, so far as the requirements relate to matters under his control – Any duty imposed on the responsible person shall be imposed on every person who has to any extent control of those premises so far as the requirements relate to matters under his control Responsible Person Duties The responsible person must make and give effect to such arrangements, having regard to the size of the undertaking and the nature of activities for effective: – Planning – Organisation – Control (planning and implementation) – Monitoring – Review 11
Responsible Person Duties The responsible person must ensure that: – The premises are, to the extent as is appropriate, equipped with appropriate Fire fighting equipment Fire detectors Alarms – Any non-automatic fire fighting equipment is Easily accessible Simple to use Identified with appropriate signage Delegate Exercise In your allocated syndicates make a list of what the Responsible Person under RRFSO will need to ensure is carried out in order to ensure that safety risks are managed with regards to Fire RRFSO Articles 8-22 Duty to take general fire precautions 8. Risk Assessment 9. 10. Principles of prevention to be provided 11. Fire safety arrangements 12. Elimination/reduction of dangerous substances risks 13. Fire fighting and fire detection 14. Emergency routes and exits 15. Procedures for serious and imminent danger and for danger areas 16. Additional emergency procedures in respect of dangerous substances 17. Maintenance 18. Safety assistance 19. Provision of information to employees 20. Provision of information to employers and self-employed from outside undertakings 21. Training 22. Co-operation and co-ordination 12
Safety Assistance The responsible person must: – Nominate competent persons to implement those measures – Ensure that the number of person are adequate – Their training and equipment are adequate A person is to be regarded as competent where he has sufficient training and experience or knowledge and other qualities to enable him to implement the above measures Successful Practical Relevant Roles and Powers of Enforcement Agencies and External Agencies Element 1.3 Enforcement Authorities The fire and rescue authority for the area of the premises The Health and Safety Executive (Nuclear Installations, ships and construction sites) The fire service maintained by the Secretary of State for Defence for armed forces and MOD establishments The relevant local authority in relation to: – a sports ground designated as requiring a safety certificate under section 1 of the Safety of Sports Grounds Act – a regulated stand within the meaning of section 26(5) of the Fire Safety and Safety of Places of Sport Act 1987 A fire inspector, or any person authorised by the Secretary of State for Crown occupied property or United Kingdom Atomic Energy Authority property 13
Powers of Inspectors – Slide 1 Produce evidence of his authority. To enter any premises, without the use of force, which he has reason to believe it is necessary for him to enter and to inspect the whole or part of the premises. To make inquiries to: – ascertain whether the provisions of the RRFSO or any regulations made under it apply or have been complied with – to identify the responsible person in relation to the premises Powers of Inspectors – Slide 2 To require the production of any records (including plans): – which are required to be kept by virtue of any provision of the Order or regulations; or – which it is necessary to see for the purposes of an examination or inspection under this article; To inspect and take copies of, or of any entry in, the records; To require any person having responsibilities in relation to any premises to give such facilities and assistance with any matters or things to which the responsibilities of that person extend for the purpose of enabling the inspector to exercise any of the powers conferred; Powers of Inspectors – Slide 3 To take samples of any articles or substances found in any premises which he has power to enter for the purpose of ascertaining their fire resistance or flammability; In the case of any article or substance found being an article or substance which appears to him to have caused or to be likely to cause danger to the safety of relevant persons: – to cause it to be dismantled or – subjected to any process or test (but not so as to damage or destroy it unless this is, in the circumstances, necessary). 14
Alteration Notice – Slide 1 The enforcing authority may serve on the responsible person "an alterations notice" if the authority is of the opinion that the premises: – constitute a serious risk to relevant persons (whether due to the features of the premises, their use, any hazard present, or any other circumstances); or – may constitute such a risk if a change is made to them or the use to which they are put. Appeals to be made to a Magistrates Court within 21 days. Alteration Notice – Slide 2 An alterations notice must: – state that the enforcing authority is of the opinion that either of the conditions given in slide 1 exist; and – specify the matters which in their opinion, constitute a risk to relevant persons or may constitute such a risk if a change is made to the premises or the use to which they are put An alterations notice may be withdrawn at any time and the notice is deemed to be in force until such time as it is withdrawn or cancelled by the court. Nothing in this notice stops an enforcing authority from serving an enforcement notice or a prohibition notice in respect of the premises Enforcement Notice – Slide 1 Similar to an ‘Improvement Notice’ under HSWA 1974 If in the opinion of the inspector the responsible person has failed to comply with any fire legislation, the authority may serve that person "an enforcement notice“. An enforcement notice must: – specify the provisions which have not been complied with; and – Require that person to take steps to remedy the failure within such period from the date of service of the notice as specified in the notice. Appeals to be made to a Magistrates Court within 21 days. 15
Enforcement Notice – Slide 2 An enforcement notice may include directions to the measures the enforcing authority consider necessary to remedy the failure: – any such measures may be framed so as to give a choice between different ways of remedying the contravention. Where it is the opinion that a person's failure to comply also extends to a workplace, or employees who work in a workplace, for which they are not the enforcing authority, the notice may include requirements concerning the workplace/employees, – however, in this case the enforcing authority must consult the enforcing authority for that workplace. Prohibition Notice – Slide 1 Issue if in the opinion of the inspector the use of premises involves or will involve a risk to persons so serious that use of the premises ought to be prohibited or restricted A prohibition notice must: – specify the matters which in their opinion give or, as the case may be, will give rise to that risk; and – direct that the use to which the prohibition notice relates is prohibited or restricted to such extent as may be specified in the notice until the specified matters have been remedied. Appeals to be made to a Magistrates Court within 21 days. Prohibition Notice – Slide 2 The notice may give directions on how to remedy the matters and such measures may be framed to afford a choice between different ways of remedying the matters. A prohibition or restriction given in the notice takes immediate effect if serious personal injury is or will be imminent, Where practicable, before such a notice is served on a house in multiple occupation the local housing authority is to be notified and informed of the use which they intend to prohibit/restrict. 16
Penalties in the Criminal Courts It is for the accused to prove that all reasonable precautions and all due diligence was taken to avoid the offence. Penalties on summary conviction (Magistrates Court) an unlimited fine. If the matter is taken on indictment (a formal charge of having committed a most serious criminal offence) it could lead to an unlimited fine, 2 years imprisonment or both. Who are the various Agencies Involved with Fire Safety? Fire Authority Fire and Rescue Services Health and Safety Executive Local Authorities Environmental Agencies (EA & SEPA) Insurance Companies Fire and Rescue Act 2004 – Slide 1 Section 44 – Allows authorised employees to deal with fires, road traffic accidents and other emergencies – It gives power to “do anything he reasonably believes to be necessary” in relation to extinguishing or preventing fires including entering a premises by force without consent. So what powers will they have? 17
Fire and Rescue Act 2004 – Slide 2 Section 45 – Enter premises at any reasonable time to obtain information needed for fire fighting, dealing with road traffic accidents and specified emergencies Cannot be forcible and 24 hours notice must be given for a private dwelling, unless authorised by a Justice of the Peace – Can take with him any other person or equipment that he considered necessary – Be provided with any facilities, information, documents or records or other assistance, that he may reasonably request Fire and Rescue Act 2004 – Slide 3 Section 45 (continued): When investigating fires, in exercising his powers, an authorised officer can additionally: – Carry out inspections, measurements and tests in relation to the premises, or to an article or substance – Take samples of articles and substances – Dismantle an article found on the premises – Take possession of an article or substances: Examine it and do anything he has the power to do Ensure that it is not tampered with before his examination Ensure that it is available for use as evidence in proceedings Fire Authority Responsible for enforcing RRFSO 2005 Also responsible for: – Promoting community fire safety – Planning and implementing procedures to fight fires etc – Rescuing people from road traffic accidents – Responding to emergencies such as flood, terrorist incidents etc. – Equip and respond to events beyond core functions such as rope rescue Can agree to the use of its equipment or personnel for purposes it believes appropriate and whenever its so chooses 18
Non-Executive Directors of HSE Acts on behalf of the government Identifies the need for legal requirements, arrange drafts and consultation Influence law from the point of view that they decide what laws are appropriate and when they are to be introduced Control the quantity of law and the scope/extent of a given law They can be lobbied by organisations with aim to gain modifications or delay Health and Safety Executive Appointed as an enforcing authority under RRFSO 2005 for: – Nuclear installations – A ship, including Navy, which is in the course of construction, reconstruction or conversion or repair by persons who include persons other than the master and crew of the ship – Construction sites Local Authorities A local authority is appointed as an enforcing authority under the RRFSO for: – A sports ground designated as requiring a safety certificate under Section 1 of the Safety of Sports Grounds Act 1975 – A regulated stand within the meaning of section 26(5) of the Fire Safety and Safety of Places of Sport Act 1987 The LA has a duty under article 45 of the RRFSO, to consult with the fire authority before passing plans to erect a building, deposited with them in accordance with building regulations. 19
Environmental Agency (EA) / Scottish Environmental Protection Agency (SEPA) Both agencies are concerned with protecting and improving the land, air and water environment RRFSO imposes a duty on the responsible person to mitigate the effects of a fire on anyone on the premises or in the vicinity of the premises If a fire causes pollution it will be of interest to the EA/SEPA Fire authorities and EA/SEPA usually work in conjunction with each other with the EA/SEPA making available to the fire authorities environmental damage limitation equipment. Insurance Companies Have become increasingly aware they may have under-estimated the risks of fire in companies they insure This has meant they have reviewed factors that have led to claims Their findings have been used to influence organisations to improve their fire safety to reduce the level of risks Successful Practical Relevant Key Features of a Fire Safety Policy Element 1.4 20
Fire Safety Management Framework The RRFSO imposes a legal duty on the responsible person to put into place safety arrangements The arrangements must take into account the size and nature of activities. These arrangements must include: – Planning – Organisation – Control – Monitoring – Review Management Models There are three (effective for NEBOSH April 2015) management model systems commonly used: – OSHAS (ISO) 18001 – BS 8800 – HSG 65 All ostensibly the same. OSHAS 18001 Model Initial Review Policy Planning Continual Improvement Implementation and Operation Checking and Corrective Management Actions Review 21
BS 8800 Model Initial and periodic status review Policy Audit Organising Planning and Implementation Measuring Performance HSG65 - The Management of Health and Safety Risk Planning Profiling Organising Policy Implementing PLAN DO Measuring Learning CHECK ACT Performance lessons Investigating Accidents, Reviewing Incidents performance Etc. Policy for Fire Safety Management Setting Policy – The policy for fire safety management is usually scoped within the organisations overall health and safety policy – It is good practice to give a senior manager the overall responsibility for fire safety management. – However, it should be remembered that the ‘responsible person’ cannot absolve their responsibility as defined in the RRFSO 22
Organising for Fire Safety Management Arrangements: – Must be in place for the effective planning, organisation, control, monitoring and review of preventive and protective measures and encompass consultation with employees; must be recorded if: There are 5 or more employees A licence under an enactment is in force An alterations notice is in force – They must be flexible enough to allow for change and may cover such areas as: Responsibility for fire safety at board level Responsibility for each premises Arrangements for appointing people to carry out specific roles in the event of a fire Monitoring and Reviewing In order to ensure that the implemented plan for fire safety is effective it needs to be monitored Monitoring should not rely solely on reactive monitoring of actual/potential fire incidents, but should include proactive monitoring A mixture of proactive monitoring methods can be utilised, including inspections, maintenance checks and meetings Proposed and actual changes in premises, people, materials and processes should be monitored to see if amendments to the arrangements are required Planned reviews should also be undertaken to follow fire incidents, proposed changes and after a period of time if not done for another reason Auditing Auditing is imperative and should be carried out by an independent party, be systematic and cover all aspects of the fire safety policy It should examine the standards and compliance with them within the management system for fire safety More than a physical inspection, it checks on the policy, the organisation for implementing the policy, individuals responsibilities, procedures including those for monitoring and reviewing, records etc. The frequency of auditing will depend on the level of risk relating to the premises 23
Fire Log Book Contents? Record all outcomes from fire prevention arrangements, including: – Contact details for maintenance and servicing engineers – Records of visits from Fire Officers – Records of maintenance/servicing of fire equipment (alarms, appliances etc.) Record of staff training – – Record of fire drills Record of actual fire alarm activation (including false alarms) – – Record of fire alarm tests Record of emergency lighting checks – – Record of fire fighting appliance checks – Record of briefings on fire precautions and safety Copy of the fire risk assessment – – Copies of fire safety plans – Copies of audit reports. Successful Practical Relevant Sources of External Fire Safety Information Element 1.5 Sources of Information ~ 1 Legislation from: – www.opsi.gov.uk Approved Codes of Practice from: – www.hse.gov.uk British Standards Building Regulations (Part B) Local Government Websites Fire Authority Websites 24
Sources of Information ~ 2 Fire safety guides on: – www.communities.gov.uk/fire From fire safety organisations on such websites as: – www.arsonpreventionbureau.org.uk – www.bre.co.uk – www.ife.org.uk – www.means-of-escape.com – www.thefpa.co.uk Successful Practical Relevant The Purposes and Procedures for Investigating Fires in the Workplace Element 1.6 Fire Investigation Purpose of investigating? – The responsible person may want: To determine the cause and preventative measures to be put into place to prevent recurrence To gather evidence because of the prospect of civil and/or criminal litigation – The Fire and Rescue Services may investigate to gather evidence in order to lay a criminal charge against the responsible person – An insurance company may investigate to determine if they have a liability for any claim arising from the fire 25
Non-Fatal Fire Investigation Covers events such as accidental and arson fires as well as false alarm Important to investigate because: – Can learn from events that have not caused harm – Can make improvements before an injury or fatality happens – It provides a valid test of preventative and protective arrangements – Gives an opportunity to review planning and implementation procedures – Repetitive false alarms can undermine the credibility of the system (need to ensure people have confidence in the system) Fire and Rescue Service would also investigate and results would be incorporated into national statistics Procedural Differences & Definitions 1 Accidental fire investigations: – If arson not suspected a fire would be considered to be accidental (someone could still be held responsible for it) – The enforcing authority (EA) would determine the causes of the fire and determine if there were breaches sufficient for enforcement action – Police do not need to be involved as EA have the power to prosecute Fire investigation is divided into various stages: – Interviewing eye witnesses – Evaluation of evidence – Locating the seat of the fire – Review of findings – Excavating the seat – Report Procedural Differences & Definitions 2 Arson set fires (non-accidental): – May be categorised as ‘malicious’, ‘deliberate’ or ‘doubtful’ – Deliberate ignition only has to be suspected not proven to categorise a fire up from ‘doubtful’, Arson or malicious fire investigation: – Investigated by fire and rescue authority – Conducted as a formal fire investigation to determine the cause – Specialist officer involved working in partnership with police and may involve a police forensic scientist – Police have to prove persons behaved ‘recklessly’ or ‘intended to damage property’ to record an offence of arson – ‘Malicious’ firing only considered arson if life is put in danger 26
Investigation Preparation Investigation may start before the fire is extinguished Important not to disturb the scene of the fire any more than necessary May have an impact of fire fighting methods used If the fire results in death or arson suspected the fire fighting may be stopped or amended to allow initial investigation to take place before the evidence is ruined Investigation and Other Agencies 1 Police: – Responsible for the criminal investigation of arson or suspicious fires – They will liaise with the Fire and Rescue Services (FRS) – May have contact with them regarding the fire risk assessment and security issues Fire & Rescue Service (FRS): – Has the power to investigate fires (powers already covered) – You have a duty to assist fire officers in their investigation – May need to speak to fire officers when carrying out the fire risk assessment regarding various issues e.g. COSHH – FRS may assess the risk to their employees in larger high risk premises and visit as part of this process Investigation and Other Agencies 2 HSE: – May contact re fire risk assessments e.g. construction sites Public Utilities: – May need to discuss issues re drainage, water pollution, fire water run offs etc especially if dangerous substances might be involved – Utilities that might be involved include: Water Supply Company Sewerage Company Electrical Supply Company Gas Supply Company Telecommunications Company Insurance Companies – to determine liability etc 27
Identifying Reasons / Remedial Action Detection of crime Verification of insurance claims Prevention of future fires Identification of defective components Identification of dangerous substances To gather evidence of a coroners office To determine reasons for false alarms To identify additional preventive/protective measures To find weaknesses in fire management system To ensure everything ‘so far as is reasonably practicable’ has been done to prevent recurrence Site and Damaged Area Clean Up Important to ensure health and safety of those involved Structure may be unstable Services may be exposed and substances released Site may be similar to a building left unoccupied a long time Pre-demolition survey may be needed Specialist companies may be needed to assist in the clean up Successful Practical Relevant Legal and Organisational Requirements for Recording and Reporting Fire Related Incidents Element 1.7 28
Post Fire Management If an organisation suffers a fire incident, there will be certain actions taken dependent on the scale of the fire and if any injury occurred. The responsible person will need to ensure that fires are reported because of: – Statutory requirements; and – Non-statutory reasons Non-Statutory Reasons The reporting of the incident would enable resources to be allocated for an investigation The investigation in turn, should help to identify flaws with existing controls and therefore assist in the implementation of improved controls Analysis of reports may identify trends or patterns Gathering statistical data will help the ‘responsible person’ and, if the Fire and Rescue Services request the data may assist in development of national statistics to identify trends and comparisons. To review fire safety risk assessments Recording of Incidents, Injuries and Dangerous Occurrences Accident book: – If an injury has occurred due to a fire (e.g. smoke inhalation) it should be reported and recorded in the accident book General incident or occurrence book: – May be kept to record various events relating to fires – Important if false fire alarm operations, near misses or fires occur on a frequent basis – May reveal trends/patterns and help identify improvements 29
Statutory Requirements If a person was injured the ‘responsible person’ may have to determine if it is reportable under RIDDOR 2013 It is an implied requirement under RRFSO 2005 Article 11 to have arrangements to monitor preventive and protective measures To provide evidence in any legal action that may be taken The ‘responsible person’ must comply with the requests of the fire service investigating officer and supply such assistance and information as required. Successful Practical Relevant NEBOSH Fire Certificate Principles of Fire and Explosion Element 2 Element 2 Learning Outcomes Explain the principles of the combustion process in relation to fire safety Explain the principles and conditions for the ignition of solids, liquids and gases Identify the classifications of fires Describe the principles of fire growth and fire spread Outline the principles of explosion and explosive combustion. 30
Successful Practical Relevant The Principles of the Combustion Process in Relation to Fire Safety Element 2.1 The Fire Triangle A fire requires: Ignition – Any heat build up or a spark can start a fire Fuel – All fires require some kind of fuel, from petrol, material, fats or chemicals Oxygen – Without oxygen a fire cannot be sustained Methods of Extinguishing a Fire Cooling – Cooling the fire to remove the heat, e.g. water Starving – Starving the fire of fuel, e.g. isolation of gas supply Smothering – Smothering the fire by limiting its oxygen supply, e.g. foam extinguisher Chemical Interference – Interference of the flame reactions, e.g. method by which some extinguishing media works. 31
The Combustion Process Once combustion has been initiated it will be self- supporting if the heat released by the combustion process enables the reaction to continue. It will continue with a supply of: – Fuel; – Oxygen; and – Heat Combustion, therefore, is a complex dynamic process, and fires may burn either with or without flames Combustion of Methane Gas Combustion can be expressed as a chemical equation. An example involving a molecule of methane gas (CH 4 ), which happens every day on domestic gas cookers would look like this: CH 4 + 2O 2 = CO 2 + 2H 2 O – 890 kJ The equation is balanced and represents the complete combustion of methane. This means that 1 molecule of methane and 2 molecules of oxygen react to become 1 molecule of carbon dioxide and 2 molecules of water with 890 kilojoules of energy given off in the form of heat and light – (released heat energy is always expressed as a negative) Combustion of Methane Methane + oxygen + heat energy supplied = carbon dioxide + water – heat energy released 32
Exothermic Reactions Reactions that release heat are called exothermic reactions Combustion, therefore, is an exothermic (gives off heat) reaction of a substance with an oxidiser (normally oxygen). The reaction requires an input of energy to initiate it. This energy comes from a source of ignition heat e.g. a spark Complete Combustion Complete combustion, where all oxygen is consumed in the combustion reaction, is the most efficient combustion of fuel. This occurs at the stoichiometric concentration – i.e. when the fuel / oxygen ratio is ideal The blue flame burning on a gas cooker with no smoke or yellow flames are an example of the complete combustion process. Incomplete Combustion Complete combustion in uncontrolled fires is rare as very often flames are relatively starved of oxygen, leading to incomplete combustion. Incomplete combustion of organic materials leads to the production of tarry and sooty decomposition products, i.e. smoke is formed Smoke is a heated mixture of air, gases and particles. Carbon monoxide (CO) is also formed during incomplete combustion 33
Carbon Monoxide Carbon monoxide is a colourless, odourless and tasteless gas usually found wherever incomplete combustion occurs, e.g. domestic boilers, vehicle exhausts, furnaces and steelworks. It is a toxic, flammable and explosive gas. Inhalation of the gas results in headaches, drowsiness, a flushed ‘pink’ appearance and ultimately in asphyxiation. Asphyxiation by Carbon Monoxide Carbon monoxide is more readily absorbed by the haemoglobin, the oxygen carrying part of the red blood cell, forming carboxyhaemoglobin. The supply of oxygen to all body organs, including the brain is therefore impaired. Stages of Combustion There are three stages to combustion: – Induction – Growth – Decay 34
Stages of Combustion - Induction Induction – Incipient Stage - At this stage, decomposition is occurring at the surface of the fuel due to the influence of some form of heat. Products of combustion given off at this stage are invisible to the eye. – Smouldering Stage - At this stage, up to 10% of the decomposing products released at the surface of the fuel are visible. The time required for a fire to develop through these stages is usually quite long when compared to the growth stage Stages of Combustion - Growth Growth – Flaming Stage (ignition) - Vapours from the decomposing fuel have ignited and are at the stage where flames are self propagating. – Heat Stage - At this stage the burning has progressed to the point where the fire is still small but generating sufficient heat to warm the air immediately around the fire, sending warm products of combustion upwards by convection. Depending on conditions, the time involved going through the induction and growth stages may be anything from seconds to days. What factors will affect the growth rate of a fire? The rate of fire growth is influenced by: Supply of oxygen Percentage of oxygen present Quantity of fuel available Physical state of the material (e.g. solids require more heat input) Volatility (vaporisation) of solid and liquid fuels Calorific value of the fuel, i.e. the heat liberated Rate of heat transfer to other fuel sources Containment of heat; and Fuel / oxygen concentration, which is ideal at the stoichiometric value 35
Stages of Combustion Steady State and Decay Steady state: – Reached when the fuels that are present within the fire area are burning at their full potential due to being fed with sufficient oxygen to sustain their maximum burn rate. A fire will decay when: – The source of fuel (combustible materials) diminishes – When the levels of oxygen diminishes – When the intensity of the heat diminishes to a level where the fire can no longer be sustained (cooling) Basic Chemical Reactivity Endothermic: – In thermodynamics, this describes a process or reaction that absorbs energy in the form of heat. – The concept is frequently applied in physical sciences to e.g. chemical reactions, where chemical bond energy is converted to thermal energy (heat). Some examples of endothermic processes are: – Cooking food – Melting of ice – Depressurising a pressurised can Endothermic Materials Endothermic materials in passive fire protection: – Endothermic substances, both natural, e.g. gypsum, and synthetic (resin-based), swell as a result of heat exposure They are popular for use in: – Heat shielding – Fire-resistive coatings for LPG vessels – Compartmentalisation of fire in buildings, which is the cornerstone of passive fire protection. Typically, the technological basis is the conversion of hydrates (chemically bound water) into vapour, or steam 36
Basic Chemical Reactivity Exothermic: – The opposite of an endothermic process is an exothermic process, one that releases energy in the form of heat. In an exothermic reaction: – the total energy absorbed in bond breaking is less than the total energy released in bond making. – In other words, the energy needed for the reaction to occur is less than the total energy provided. – As a result of this, the extra energy is released, usually in the form of heat. Exothermic Reactions Example exothermic reactions: – Combustion reactions Neutralisation reactions for instance direct reaction of acid and base Adding water to concentrated acid Adding water to anhydrous copper sulphate – Thermite reaction Reactions taking place in a self-heating can based on lime and aluminium Successful Practical Relevant The Principles and Conditions for the Ignition of Solids, Liquids & Gases Element 2.2 37
Identification of Sources of Ignition Majority of fires need a source of ignition to start. It is imperative, therefore that an assessment should be made to identify possible sources of ignition in a workplace. Once these have been identified then the area can be checked for combustible materials. Once problem areas have been identified, a study can be made to assess viability of separating the two. If this is not possible some form of control measure should be taken to minimise the risk of a fire. Principles of Fire and Explosion The physical state of a substance and its ability to mix with oxygen affect its flammability Flammable Materials Most organic (carbon containing) solids (and dusts), liquids and gases are flammable e.g.: – Chemicals; – Electrical equipment; – Paper, card and wood; – Plastics, rubber and foam; – Furniture and textiles; – Fixtures, fittings; and – Waste material 38
Non-Flammable Materials Most inorganic (non-carbon containing) substances are non- flammable, however, there are a few exceptions: – Aluminium – Magnesium – Titanium Above 3 used widely in aircraft/warship manufacture – Hydrogen Emitted during battery charging – Phosphorous – Sulphur Above 2 used in chemical processes Ignition of Solid Materials ~ Slide 1 The ease with which a solid will ignite depends upon the type of material and its physical state. The smaller the particles of material, the easier it is to ignite e.g. A pack of A4 paper will not ignite readily as it is packed – sheets with no air in the middle; – Separate the sheets and each sheet will be easier to ignite; – Shred the pack of A4 paper and it will have lots of air in the middle and again it will be easier to ignite. When looking at sources and ignition we need to consider the physical state of any potential fuel. Ignition of Solid Materials ~ Slide 2 Solid material does not actually burn When involved in a fire the solid will first chemically decompose and produce carbon products in the form of a vapour It is these vapours that ignite when mixed with oxygen from the air: Hold a lit match to a piece of paper: – It will be seen that the paper does not burst into flames, but chars and goes black Vapours are given off and it is these that burn 39
Ignition of Liquids & Gases A flammable liquid gives off vapours and it is these that ignite The temperature and rate at which vapours are given off will vary from one flammable liquid to another Flammable liquids that more readily release vapours are said to be more volatile than others Some liquids, such as petroleum, readily give off vapours at room temperature Others, such as diesel oil, need to be heated before they give off sufficient vapours to be a significant risk. Conditions for Ignition to Occur Ignition occurs when a heat source e.g. a spark, contains sufficient heat energy to cause combustion of one or more molecules of a flammable vapour or substance. To avoid ignition the simple principle of separating the heat and fuel sources can be used. Heat Energy Definitions Ignition heat energy has 3 measurements: – Flash point – Fire point – Auto-ignition temperature Other definitions we need to know are: – Vapour pressure – Vapour density; and – Flammability limits 40
Flash Point This is the minimum temperature where flammable vapours are capable of being ignited momentarily by an outside source of heat, e.g. a spark etc. At this temperature, the ignited vapours will flash but will not continue to burn. Combustion cannot continue as there is insufficient heat generated to replace the vapour that has ignited. The flash point of a vapour or gas is one measure of its fire potential. The lower the flash point the greater the hazard. Fire Point The fire point of a fuel is the temperature at which it will continue to burn after ignition for at least 5 seconds. At the flash point, a lower temperature, a substance will ignite, but vapour might not be produced at a rate to sustain the fire. Fire point is the lowest temperature at which a fuel will produce sufficient vapours to form a mixture in air that continuously supports combustion after ignition. Auto-ignition Temperature The temperature at which combustible materials ignite spontaneously in air without a spark or flame being present. Common fuels auto-ignition temperatures: 400 o C – Petroleum – Wood 300 o C – Kerosene 215 o C 480 o C – Propane – Methane 580 o C 41
Vapour Pressure Vapour pressure is a measure of the tendency of a material to form a vapour. The higher the vapour pressure, the higher the potential vapour concentration and the more likely it is to be a fire hazard (they are more volatile) than a similar material with a lower vapour pressure. The higher the vapour pressure of a material at a given temperature, the lower the boiling point. The boiling point is the temperature where the vapour pressure equals the ambient atmospheric pressure. All solids and liquids have a tendency to evaporate to a gaseous form, and all gases have a tendency to condense back to their liquid form. Other Definitions Vapour density: – The density of a gas relative to the density of hydrogen or air at the same temperature and pressure. – Worked out by using molecular weights of the atoms concerned. – The figure of vapour density is of little value as it is a theoretical comparison to hydrogen. Relative density: – Is the ratio of the specific density of a substance to the specific density of a standard substance under specified conditions. – For vapours and gases, the standard is often air at the same temperature and pressure. – If the relative density is less than 1, it makes it lighter than air and if greater than 1, heavier than air and likely to sink to a lower level. Other Definitions Flammable limits: – Gives the fractions of combustible gases in a mixture, between which limits this mixture is flammable. – Gas mixtures consisting of combustible, oxidising, and inert gases are only flammable under certain conditions. – The lower flammability limit (LFL) describes the leanest mixture that is still flammable, i.e. the mixture with the smallest fraction of combustible gas. – The upper flammability limit (UFL) gives the richest flammable mixture. – Increasing the fraction of inert gases in a mixture raises the LFL and decreases UFL. 42
Successful Practical Relevant Classifications of Fires Element 2.3 Classifications of Fires Fires are classified into five categories The category of a fire determines the methods by which the fire may be tackled to extinguish it What type of fire extinguishers that can be used to put out a fire is also dependent on the category Fire extinguisher signage also denotes the category of fire on which the extinguisher is safe to use Class A Free burning carbonaceous materials such as paper, wood, card, cloth, rubber, etc. The extinguishing mode is by cooling the heat / ignition source 43
Class B Class B is for burning liquids. It breaks down into two separate classes: – B1 - liquids soluble in water (miscible) such as methanol. These can be extinguished by smothering or cooling – B2 - liquids insoluble in water (immiscible) such as petrol and oils. These can be extinguished by smothering Class C Fires that involve flammable gases or liquefied gases resulting from leaks or spillage These are extinguished by smothering or starving by removing the fuel if safe to do so Class D These are specialist fires that involve metals such as Aluminium or Magnesium. These are extinguished by smothering with graphite or talc. 44
Class F Covers high temperature cooking oils and fats in large catering establishments or restaurants. These are extinguished by isolating the source of heat and smothering the fire. Electrical Fires Not a class of fire Could be involved in any class of fire It may be present as a cause, ignition source or separate hazard Successful Practical Relevant Principles of Fire Growth and Fire Spread Element 2.4 45
Principles of Heat Convection Transmission and Fire Spread Radiation Conduction Direct burning Spread of Fire Conduction - spread of heat energy through solids; Convection - heat transfer through a fluid or gas, involving expansion and movement; Radiation - emission of heat energy through electromagnetic radiation in the infra-red part of the spectrum, which is then absorbed by matter to varying degrees Direct Burning – combustible materials catching fire through direct contact with flames. Common Building Materials When considering the type of building material to be used and its application the following criteria should be assessed: – For safety of people: Ignitability Flammability Surface spread of flame Smoke (or gas) release. – For safety of the building: Heat release Fire resistance Flame penetration Smoke (or gas) penetration. 46
Classification of Building Materials The class of a material indicates the speed of surface spread of flame across that material. The classes (class 0 the best) are: – Class 0 (plasterboard, woodwool slabs, mineral fibre board) – Class 1 (wood treated with a fire retardant coating) – Class 2 (wood pressure treated with fire retardant) – Class 3 (chipboard, plywood, hardwood timber) – Class 4 (soft-board, softwood timber) Class 0 is not a true classification, but to be in Class 0 a material must be Class 1 and must not contribute greatly to the propagation of the fire. Concrete Strong in compression, but weak in tension - will be reinforced with steel in areas where it will be subject to stress (e.g. lower part of a concrete beam) The fire resistance of concrete is influenced by: – Size and shape of element – Disposition and properties of reinforcement – The load supported – Type of concrete and aggregate – Conditions of end support Steel reinforcement when heated up will loose strength For mild steel 50% of its strength is lost at 550 o C, for high temperature steel this point is at 600 o C (critical temperature). Metals Metals may need surface protection to reduce risk of fire spread via conduction All metals soften and melt at high temperatures Unprotected steel may give rise to danger of collapse in a fire when it is heated to a rds of its strength temperature where it has lost 2 / 3 Metals expand when heated The expansion in a long beam could be enough to push out walls leading to structure collapse 47
Metals ~ Aluminium Alloys Advantages: rd the weight of steel) – Reduction in weight ( 1 / 3 – Resistance to corrosion – Ease of working and handling – High strength to weight ration Disadvantages: – Very rapid loss of strength in a fire (100 o C to 225 o C) – High expansion rate (twice that of steel) – High thermal conductivity (3 times that of steel) – Low melting points (658 o C for pure aluminium) Protection of Metal Structural Members The following methods can be used to protect metal structural members: – Solid protection Sprayed or applied mineral coating Intumescent coatings – Hollow protection Hollow section filled with water Using lightweight blocks of concrete to fill hollow webs of beams – Design features such as fire retardant suspended ceilings Intumescent Materials An intumescent is a substance which swells as a result of heat exposure, thus increasing in volume, and decreasing in density. Intumescents are typically endothermic to varying degrees, as they can contain chemically bound water Intumescents are used in fire-stopping and fire-proofing applications in buildings 48
Sandwich Panels Normally consists of two outer skins of sheet metal (a light alloy) with an infill of heat insulating material (e.g. polyurethane or styrene foam) Use giving rise to great concern: – Buildings constructed of sandwich panels are liable to sudden, unpredictable collapse when a fire occurs – Panels falling out of their framework further accelerate spread of fire – Exposed/heated foam breaks down into volatile flammable toxic gases Fire brigades tend to use a non-attack strategy Plastics There are two basic types: – Thermoplastics which when heated will soften and melt – Thermosetting; sets to a hard infusible form Plastic materials are composed of combustible organic material Have limited resistance to fire and fire spread Most when exposed to fire emit a considerable amount of smoke and toxic fumes Glazing Materials Non-combustible material Will not contribute to the fire load (amount of combustible material) of a building Standard glass panels in doors/walls create a weak point in fire compartmentation Fire resisting glazing can give up to 1 1 / 2 hours fire resistance Wired glass (usually 6mm thick and up to 1.6 m 2 in area) can give up to 1 1 / 2 hours fire resistance Laminated glass (Pyran) comprising of 3 to 5 layers of glass with interlayers of intumescent material which reacts at 120 o C to form an opaque shield and prevents radiated heat from passing through 49
Effects of Building Construction In addition to the materials used to construct the building, the actual construction of a building can increase the risk of fire growth e.g.: – Large open areas with little of no fire compartmentation and can result in flashover – Voids behind wall panelling – False ceilings with open voids above – Vertical shafts such as lifts – Open stairwells – Doors that are ill-fitting, damaged or wedged open – Holes in fire resistant structures (to permit pipes and cabling to be installed) Effects of Contents HSG 64 “Assessment of Fire Hazards from Solid Materials” materials are categorised into high and normal risk. The risk category is determined by the amount of smoke produced by the material and maximum rate of temperature rise. Items that scored as high risk in both tests include: – Acrylic fibre – Acrylic mixture – Acrylic over locks – Expanded polystyrene – Flexible polyether (Poly Urethane foam) – Polypropylene sliver – Rigid Poly Urethane foam (low density) Open Burning Fire A fire burning outside of a building: – Hot gases of combustion will rise into the atmosphere – Will not have much effect on the materials involved in the fire As a result, the speed of fire growth is generally slower than it would be in a confined space 50
Physically Enclosed Burning Fire Heat and gases build up will have a greater effect on the material involved in the fire The speed of fire growth can be devastating Two specific phenomena contributing to fire growth are: – Flashover – Backdraught Flashover Can occur if a fire is free burning in a room – Must have a good supply of air e.g. large room, open door, open window or ventilation system The radiated heat heats up all other material in the room until they reach their spontaneous ignition temperature Items in the room instantly ignite Gives impression that the fire has ‘flashed over’ from one side of the room to another Backdraught To occur a fire must start in a closed room environment (doors/windows closed & little air flow) Burning fire will use up oxygen in room Fire will die down, but often does not go out A smouldering fire remains that fills room with high temperature smoke (flammable gases mixed with fuel particles that would normally be burnt off) If someone opens a door, oxygen is allowed to enter and the flammable gas/fuel can instantly ignite if they are at their spontaneous ignition temperature If it happens, it will be with an explosive force driving flames out of the opening at 10 m/sec and 1100 o C 51
Smoke Spread in Buildings Cold smoke will spread laterally, possibly at low level, with a principle hazard of low visibility Hot smoke: – Is a fuel above its ignition temperature and will spontaneously combust when it reaches available oxygen. – It will be carried with the convection current produced by the combustion process – It will spread laterally across the ceiling then upwards at every opportunity – Due to its buoyant nature, it can travel a considerable distance from the seat of the fire Smoke Smoke consists of: – Unburnt carbonaceous material – Gases that are both flammable and toxic The majority of gases in smoke will be: – Carbon monoxide – Toxins such as hydrogen chloride from combustion of electrical conductor insulation – Cyanide compounds from combustion of synthetic upholstery form infill These gases will quickly render people unconscious and cause death, which could explain why – The majority of people who die from fires that occur when they are asleep tend not to attempt to escape Successful Practical Relevant Principles of Explosion and Explosive Combustion Element 2.5 52
Explosions and Definitions ~ 1 Explosion: – an abrupt oxidation, or decomposition reaction that produces an increase in temperature, or pressure, or in both temperature and pressure simultaneously. Explosive Atmosphere: – flammable substances in the form of gases, vapours, mists or dusts mixed with air under atmospheric conditions, which, after ignition has occurred, combustion spreads to the entire unburned mixture. Explosions and Definitions ~ 2 Deflagration – process of subsonic combustion that usually propagates through thermal conductivity (hot burning material heats the next layer of cold material and ignites it). Detonation – process of supersonic combustion in which a shock wave is propagated forward due to energy release in a reaction zone behind it. It is the more powerful of the two general classes of combustion, the other being deflagration Explosions and Definitions ~ 3 BLEVE – Boiling Liquid Expanding Vapour Explosion: – an explosion due to the flashing of liquids when a vessel with a high vapour pressure substance fails CGE – Confined Gas Explosion: – explosion within tanks, process equipment, sewage systems, underground installations, closed rooms, etc. UVCE – Unconfined Vapour Cloud Explosion: – a vapour/gas explosion (deflagration or detonation) in an unconfined, unobstructed close 53
Mechanism of Explosion An explosion is the “rapid flame propagation throughout an area containing flammable gases, vapours and other dusts”. The substance has to be mixed with air in such proportions that the mixture is within flammability range of the substance. Gas/vapour/dust clouds can be ignited and cause explosions in both confined and unconfined states. Gas/Vapour/Dust Cloud Ignition ~ 1 When a cloud is ignited, the flame can propagate in two different modes through it. These modes are: – Deflagration – Detonation The most common mode is deflagration. During deflagration the flame front travels at subsonic speeds through the unburned gas; typical flame speeds do no reach higher than 300m/s. The pressure developed in front of the flame explosion may reach values of several bars. Gas/Vapour/Dust Cloud Ignition ~ 2 The speed of travel of the flame front during detonation is supersonic. In a fuel/air cloud a detonation wave will move at speeds of between 1500 and 2000m/s and the peak pressure in front of the flame can reach 15 to 20 bar. The pressure front when enclosed can cause substantial damage including the collapse of structures. Where ignition of the cloud is from a weak source e.g. a hot surface, the ignition will initially start as a slow burning deflagration. When deflagration becomes sufficiently rapid, a sudden transition to detonation may occur. 54
Explosions Unconfined explosions can cause devastation over a large area (e.g. Buncefield explosion) Explosions can occur with such gases as hydrogen, propane and acetylene. Dusts that can also be sources of explosions include aluminium, coal, flour and polythene. In a dust explosion, there is an initial smaller “Primary Explosion” which is then followed by a devastating “Secondary Explosion”. Lower & Upper Explosion Limits The explosive limit of gases/vapours, is the limiting concentration (in air) that is needed for the gas to ignite and explode. There are two explosive limits for any gas or vapour: – lower explosive limit (LEL) & upper explosive limit (UEL). At concentrations in air below the LEL there is not enough fuel to continue an explosion; At concentrations above the UEL the fuel has displaced so much air that there is not enough oxygen to begin a reaction. Concentrations of explosive gases are often given in terms of percent of lower explosive limit (%LEL). Conditions for Gas Explosions The atmosphere into which the gas is dispersed must contain sufficient oxidant to support combustion The gas must have a concentration within the explosive range (LEL and UEL) The gas cloud must be in contact with an ignition source of sufficient energy to cause ignition 55
Conditions for Dust Explosions ~ Slide 1 The dust must be explosible The dust must have a particle size distribution that will allow propagation of flame The atmosphere into which the dust is dispersed as a cloud or suspension must contain sufficient oxidant to support combustion The dust cloud must have a concentration within the explosive range The dust cloud must be in contact with an ignition source of sufficient energy to cause ignition Conditions for Dust Explosions ~ Slide 2 Dust particles larger than 400µm are not combustible. Particles are combustible when they measure from 20µm and up to 400µm Dust is combustible within certain concentration parameters: – lower combustibility limit: approx. 20 to 60 g/m 3 air – upper combustibility limit: approx. 2 to 6 kg/m 3 air Dust Explosions – Types of Material The types of material that often cause dust explosions include: – Coal and peat – Metals such as iron, zinc, aluminium – Natural organic materials such as grain, lime, sugar etc. – Process materials such as plastics, organic pigments (paint), pesticides etc. 56
Classification of Explosions An explosion that occurs within vessels, pipes, tunnels or channels will be classified as a confined gas explosion (CGE) An explosion which occurs in process plants or unconfined areas will be classified as an unconfined vapour cloud explosion (UVCE) Where the cloud is formed by a liquid rapidly expanding from a ruptured vessel which is substantially above is boiling point (e.g. liquid methane in a tanker which is on fire), that is then ignited causing it to detonate, is classified as a Boiling Liquid Expanding Vapour Explosion (BLEVE) Principles of Explosion Management These principles are given in of The Dangerous Substance and Explosive Atmospheres Regulations (DSEAR): – Reduce quantity of dangerous substances held – Avoid or minimise the release of the substance – Control of the release at source – Prevent of the formation of an explosive atmosphere (includes ventilation) – Ensure any release is suitably collected, safely contained and removed to a safe place or rendered safe – Avoid ignition sources in area and adverse conditions which could give rise to harmful physical effects – The segregation of incompatible substances. Principle of Gas/Vapour Explosion Suppression Controlling gas and vapour concentrations outside the explosive limits is a major consideration in occupational safety and health. Methods used include use of: – Dilution ventilation; – Sweep gas, an inert gas such as nitrogen or argon to dilute the explosive gas before coming in contact with air; – Scrubbers or adsorption resins to remove explosive gases before release are also common. Gases can also be maintained safely at concentrations above the UEL, although a breach in the storage container can lead to explosive conditions or intense fires 57
Principle of Dust Explosion Suppression Controlling sources of ignition (covered later) Inerting: – The addition of inert substances to either the dust or the atmosphere to prevent the formation of explosible dust clouds Typical equipment in which explosions are prevented by inerting are: – Enclosed reactors, mixers, mills, dryers, oven filters and dust collectors – Hoppers and silos – Conveyors and bucket elevators Dust Inerting Types Diluent dust addition: – Render explosible dust non-explosible by acting as a heat sink or interfering with flame propagation (e.g. calcium sulphate, limestone, sodium bicarbonates, various silicates etc.) Use of an inert gas: – Involves the partial or complete substitution, by inert gas, of the air with which the dust is mixed. The choice of inert gas depends on a number of factors. Choices include carbon dioxide, nitrogen, argon, helium, steam, flue gases etc. Mitigating Effects of an Explosion Bursting Discs: – Plant and machinery have a bursting disc built into them. This is a weak spot that is designed to rupture at a pre- determined pressure. This will vent the pressure immediately and prevent a more damaging explosion occurring. 58
Sources of Reference and Statutory Instruments INDG 227 – Safe working with flammable substances HSG 140 – Safe use and handling of flammable liquids HSG 103 – Safe handling of combustible dusts ~ precautions against explosions FIS2 – Dust suppressions in the food industry The Classification, Labelling and Packaging (CLP) of Substances Regulations 2015 (a European Regulation) The Dangerous Substances and Explosive Atmospheres Regulations 2002 Building Regulations 2010 Approved Document B ~ Fire Safety The Regulatory Reform (Fire Safety) Order 2005 Schedule 4 Successful Practical Relevant NEBOSH Fire Certificate The Causes and Prevention of Fires Element 3 Element 3 Learning Outcomes On completion of this element candidates should be able to: – Explain the causes of fires and explosions in typical work activities; – Outline appropriate control measures to minimise fire risk 59
Successful Practical Relevant Causes of Fires and Explosion in Typical Work Activities Element 3.1 Accidental Fires Account for 57% of all fires in the UK They can be grouped into the following: – Careless actions (26%) – Misuse of equipment and appliances (24%) – Defective equipment (50%) 78% being due to faulty appliances and leads Common Sources of Ignition Smokers’ material Electrical faults Sparks from: Overloaded circuits Welding equipment Overheating equipment Electrical equipment Static Electricity Grinding equipment Use of non-intrinsically safe electrical / electronic Oxy-acetylene welding equipment Fixed or portable heaters Radiated heat from Cooking equipment legitimate sources such as Bitumen boilers light bulbs Steam pipes Hot surfaces such as soldering irons etc 60
Storage of Flammable Materials Common causes fires involving storage of flammable materials: – Lack of awareness of their properties – Operator error, due to lack of training – Inadequate or poor storage facilities – Hot work to close to containers – Exposure to heat from nearby fires – Inadequate control of ignition sources – Dismantling or disposing of containers – Inadequate design, installation or maintenance of equipment – Decanting flammable materials in unsuitable storage areas Transportation in Workplace Incidents common occur in handling operations, including: – Movement from storage or within the premises – Decanting or dispensing – Unsecured storage within a vehicle – Emptying vehicle fuel tanks – Dealing with spillages Common causes: – Lack of awareness of their properties – Operator error due to lack of training – Inadequate or poor transport facilities – Absence of spillage strategies – Electrostatic discharge – Poor design, installation or maintenance of pipe installations Smokers Material and Lightning Smokers material: – Causes 7% of accidental fires in non- residential premises – Prohibiting smoking except in designated areas is an effective control Lightning: – Strikes on buildings (especially tall ones) can cause power surges and faults in equipment an cables – Can be hazard in farms where chemical substances are stored – Protection often effected by earthing rods 61
Construction and Maintenance Work Many serious fires occur in existing buildings during maintenance and construction work Increased fire risks are present during these activities Additional fire precautions needed May be necessary to carry out new fire risk assessment to include new hazards e.g. – Additional sources of ignition – Additional sources of combustible materials Materials can obstruct escape routes if not adequately controlled Construction & Maintenance Work Issues Accumulation of flammable waste and building materials Obstruction or loss of exits and exit routes Flammable products being introduced (adhesives/gases) Materials stored in unusual locations (roof/basement) Boxes being stored in corridors Off cuts of wood and sawdust left in work areas Packing from materials Pallets and plastic covering left where materials were used Flammable liquids not controlled Bulk storage not kept outside away from buildings/sources of heat Part empty pots or tubes of adhesive Waste disposal procedures Other Possible Construction Hazards Demolition: – Flammable materials from previous use – Residues in old storage tanks – Flammable liquids/gases in confined spaces – Use of bonfires to dispose of some waste materials Use of oxy-fuel equipment: – Welding – Hot work Temporary electrical installations: – Incorrect standards/specifications for the work – Trailing cables and leads 62
Arson Statistics – England Arson – Statistics for England Each week there are on average 1,416 fires recorded as occurring in England (2015-2016 statistics) of which 372 are arson attacks. Weekly arson attacks include: – 274 secondary fires (excluding outdoor fires) e.g. fires involving refuse and single derelict buildings. – 11 outdoor fires (brush, trees, crops, grassland etc.) – 48 involving road vehicles (usually to cover a crime) – 15 in dwellings – 22 in other buildings (e.g. businesses, schools etc) Arson – Motives and Signs Signs of arson: – Multiple seats of fire – Use of an accelerant – Forced entry Possible motives: – Fire in an unnatural position – Movement of goods / – Vandalism / boredom combustibles prior to fire – Concealment of crime – Disablement of fire detection / – Insurance fraud extinguishment systems – Jealous competitor – Pyromaniac – Attention seeking 63
Arson – Influencing Factors Location of premises (many arson attacks related to general societal problems) Premises built in run down inner city area are at greater risk than those in rural areas Position of building to public roadway Frequency of people passing by Potential of building to trespass (may set fire to rubbish bins, skips, vehicles etc) Successful Practical Relevant Appropriate Control Measures to Minimise Fire Risks Element 3.2 Arson and Security Good levels of security an effective deterrent External: Internal: – Control of people having – Good housekeeping access to the building or – Inspections site – Clear access routes – Use of patrol guards – Visitor supervision – Lighting at night – Control of sub- – Safety of keys contractors – Structural protection – Audits – Site of rubbish bins at least 8m from buildings 64
Preventing Arson Management trained to be prepared for arson Perimeter security issues addressed Secured access into premises (roller shutters) Active measures (CCTV, intruder alarms etc.) Storage facilities kept away from external walls Waste bins etc kept minimum of 8m from walls Secured wheeled waste receptacles Regular disposal of waste from site Removal of dry vegetation close to premises Awareness children gaining access especially during school holidays Prevention of Fire In Use Flammable Materials In use quantities kept to a minimum, excess quantities correctly stored If large quantities used, consider piped systems Container lids always replaced after use Rags impregnated with product disposed of safely Common electrical earth bonding in areas where dispensing / charging containers with flammable materials is carried out Only trained and competent operatives to use flammable materials. Prevention of Fire Storage of Flammable Materials Keep quantities to a minimum Up to 50 litres of highly flammable liquids in a fire resisting container Use external storage – should provide 30 minutes fire resistance Keep storage areas well ventilated Store flammable liquids in a bunded area, or use a drip tray Keep empty containers separate to full ones Prevent possible external damage to storage containers Isolate damaged or leaking containers Create separation between storage containers / limit height of stacks Use of flame proof lighting in storage areas Permit only authorised access Signage and training of persons involve in storage operations 65
Prevention of Fire Transport within the Workplace If large quantities used, consider piped systems Purpose designed metal flameproof containers used to transport small quantities with lids and anti-spill features Checks on container lids before moving Palletised containers to be made secure before moving Hazard warning signs displayed on containers Common electrical earth bonding in areas where dispensing / charging containers with flammable materials is carried out Only trained and competent operatives to transport flammable materials Safe Storage V I C E S Ventilation – provide plenty of fresh air to rapidly disperse and vapours Ignition – control ignition sources Containment – use suitable containers and provide spillage control Exchange – consider whether a safer alternative can be used to do the task Separatio n – store away from process areas (physical barrier, wall or partition where possible) Housekeeping Good housekeeping will reduce the likelihood of fire Poor housekeeping not only affects the ease with which a fire can occur, develop and spread, but can lead to: – Blocked fire exits – Obstructed escape routes – Difficulty in accessing fire alarm call points, extinguishers and hose reels – Obstruction of vital signs and notices – A reduction in the effectiveness of automatic fire detectors and sprinklers. 66
Fire Safety Checks and Inspections Fire safety checks and inspections should: – Help prevent fires in the workplace – Ensure escape routes are clear of obstructions – Monitor fire safety standards – Keep staff aware of fire safety issues – Reinforce the role of employees, supervisors, managers and fire marshals Fire Safety Audit A systematic review of fire prevention arrangements should be carried out by means of an audit at agreed intervals It will be carried out by a Fire Safety Manager It will verify the quality/appropriateness of the inspection system, maintenance arrangements and understanding of the roles of those with specific responsibility The assurance of fire safety arrangements should increase as a result of having audits Safe Waste Disposal Considerations: Does waste give off flammable vapours, if so is there the potential for them to be ignited? Is the waste in a dust format and if disturbed can it create a flammable dust cloud? How easy will it be for an arsonist to gain access to the waste and ignite them? If waste is ignited, what will be the effects? Does the waste need to be removed by a specialist company? Are hazards created by current disposal methods? 67
Safe Systems of Work A system to manage residual risks after the controls identified by the risk assessment have been implemented An agreement between management and staff defining how to perform tasks safely Normally a written procedure, but can be oral depending on the level of risk involved Needs to ensure that fire hazards are not created or risks of fires occurring increased Minimising Fire Risk Safe operating procedures – Used to ensure unnecessary fire hazards or risks are not introduced Planned and preventive maintenance – Used to ensure mechanical or electrical defects are not the cause of fires Management of contractors – Contractors on site increase the risk of fires, choosing competent contractors who have a good safety record can reduce this risk. Permits to work – Most commonly used is a ‘hot work permit’ Safe Systems of Work - Considerations People: – Behavioural traits, knowledge, skill, awareness, training and level of supervision Equipment: – Safe use, suitable environment and maintenance Materials: – Type, form and exposure to possible ignition sources Environment: – Heating, lighting and ventilation 68
Existing Buildings Potential Construction Work Problems Accumulation of flammable waste and building materials The obstruction or loss of an exit or exit routes Fire doors propped open or missing Openings being created in fire resisting structures Introduction of additional electrical equipment or other sources of ignition Introduction of flammable materials e.g. adhesives Possibility of false alarms due to dust setting off detectors Covers being left off detectors close to work Disconnection of fire protective systems e.g. sprinklers Introduction of contractors into site who may not be aware of the hazards present (e.g. bypassed induction procedure) Classification, Labelling and Packaging (CLP) Regulations 2015 The regulation requires companies to appropriately classify, label and package their substances and mixtures before placing them on the market. It aims to protect workers, consumers and the environment by labelling that reflects a particular chemical's possible hazards. It also addresses the notification of classifications, the establishment of a list of harmonised classifications and the creation of a classification and labelling inventory, as required by REACH. Classification, Labelling and Packaging (CLP) Regulations 2015 Physio-Chemical Properties: Health Effects: – Acute toxicity – Explosive – Chronic toxicity – Oxidizing – Extremely flammable - FP <23 o C – Harmful – Highly flammable – FP <32 o C – Corrosive – Flammable – FP => 32 o C – Irritant – Pressurised Non-hazard – Sensitising (inhalation/skin) Environmental: – Carcinogenic (Cat 1/3) – Mutagenic (Cat 1/3) – Acute and Chronic Toxicity to the aquatic environment – Toxic for reproduction (Cat 1/3) – Hazardous to the ozone layer *FP = Flash Point 69
Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) Employers must: – find out what dangerous substances are in their workplace and what the risks are; – put control measures in place to either remove those risks or, where this is not possible, control them; – put controls in place to reduce the effects of any incidents involving dangerous substances; – prepare plans and procedures to deal with accidents, incidents and emergencies involving dangerous substances; – make sure employees are properly informed about and trained to control or deal with the risks from the dangerous substances; – identify and classify areas of the workplace where explosive atmospheres may occur and avoid ignition sources (from unprotected equipment, for example) in those areas. DSEAR Hazardous Zone Classifications Explosive atmosphere in air with gas, vapour or mist present Zone 0 continuously, or for long periods of time. Explosive atmosphere in air with gas, vapour or mist likely to Zone 1 occur in normal operations occasionally. Explosive atmosphere in air with gas, vapour or mist not likely Zone 2 to occur in normal operations, but if it does it will be for a short period only. Explosive atmosphere in air with a cloud of combustible dust Zone 20 present continuously, or for long periods of time. Explosive atmosphere in air with a cloud of dust likely to occur Zone 21 in normal operations occasionally. Explosive atmosphere in air with dust not likely to occur in Zone 22 normal operations, but if it does it will be for a short period only. Control of Major Accident Hazards Regulations 2015 (COMAH) Applicable to any establishment storing or otherwise handling large quantities of industrial chemicals of a hazardous nature. Types of establishments include chemical warehousing, chemical production facilities and some distributors. The regulations operate on two levels depending on the establishment's status which is divided into two categories, 'Lower Tier' and 'Upper Tier', determined by inventory. Lower tier establishments are required to document a Major Accident Prevention Policy (MAPP). A top tier COMAH establishment is required to produce a full safety report which demonstrates that all necessary measures have been taken to minimise risks posed by the site with regard to the environment and local populations (i.e. on site and off site emergency plans). 70
Successful Practical Relevant NEBOSH Fire Certificate Fire Protection in Buildings Element 4 Overall Aims For the candidates to be able to: Outline the means of fire protection and prevention of fire spread within buildings in relation to building construction and design; Explain the requirements of a means of escape; Outline the methods and systems available to give early warning in cases of fire, both for life safety and property protection; Outline the selection procedures for basic fire extinguishing methods for both life risk and process risk; Explain the requirements for ensuring access for the fire service is provided and maintained. Successful Practical Relevant The Means of Fire Protection and Prevention of Fire Spread within Buildings in Relation to Building Construction and Design Element 4.1 71
Building Regulations 2010 Powers to make building regulations contained in Building Act 1984 The Act provides that they may be made for the purpose of: – Securing the health, safety, welfare and convenience of persons in or about the buildings – For furthering the conservation of fuel and power – For preventing waste, misuse or contamination of water Current building regulations contain a broad range functional requirements to which building work must comply, covering: – structure, fire safety , sound insulation, ventilation, conservation of fuel and power, facilities and access for disabled people etc. They are grouped under 16 parts (A, B, C thro’ to R) Building Regs 2010 Fire Safety Approved Document B 2010 Edition Covers: B1 - Means of warning and escape B2 - Internal fire spread (linings) B3 - Internal fire spread (structure) B4 - External fire spread B5 - Access and facilities for the fire service Internal Fire Spread - B2 (Linings) Covers: – Partitions / Walls / Ceilings or Internal structures Requirement: – To inhibit the spread of fire in a building, the internal linings shall: Adequately resist the spread of flames over their surfaces; and Have, if ignited, a rate of heat release or a rate of fire growth, which is reasonable in the circumstances 72
Internal Fire Spread - B3 (Structure) Requirement: – Buildings to be designed/constructed so that, in a fire, it keeps it’s stability for a reasonable period – A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire. – To inhibit spread, buildings shall be sub-divided with fire resisting construction. – Buildings shall be designed so that the unseen spread of fire and smoke within concealed spaces is inhibited Elements of a Building Structure With a few exceptions given in the BR ‘Approved Document B’, the following are defined as structure elements: – A member forming part of the structural frame of a building or any other beam or column; – A load bearing wall or load bearing part of a wall – A floor – A gallery – An external wall – A compartment wall Requirement for Fire Resistance for Structure Elements Required to maintain the integrity of fire compartments If a service penetrates vertical or horizontal compartments it should not decrease fire resistance Fire resistant structures found in many forms: – Typical brick, block work and plaster finish structures can give in excess of 1 hours fire resistance – Hollow partition stud wall with plasterboard finish both sides will give 30 minutes fire resistance Common failing is unauthorised openings being made in the fire resistant structure Any holes made should be made good with fire resistant materials of equal or better standard than the original 73
Factors to Consider About Fire Resistance of Structure Elements Potential fire severity Building height Building occupancy Resistance to collapse – Load bearing capacity of an element also know as stability; its ability to withstand the load on it under fire conditions Fire penetration – Integrity; the ability of a structure element to prevent failure Transfer of excessive heat – Insulation of structure elements to prevent spread of fire Compartmentation Designed to prevent spread of fire from one part of a building to another Regulations limit size of compartments in certain buildings Single storey factory units can have one large compartment Achieved by use of compartment walls and floors which should withstand a fire for a minimum of 30 minutes (dependent on the purpose and use of building) Fire should be contained in the compartment by the nature of the fire resistant materials used Stairwells and ducts should also form separate compartments to prevent vertical spread Large compartments may be fitting with sprinkler systems in an attempt to limit the size and spread of fire Protection of Openings in Compartmentation Openings in fire compartmentation gives rise to the potential for fire to spread Doors are typically set into fire compartments and will need to have a degree of fire resistance Need to be in good state of repair, fit correctly and be closed in the event of a fire Steel fire shutters are another way of preventing fire spread and are often used in theatres Fire dampers in ducting to close off air ventilation and circulation systems in the event of a fire Fire dampers (shutters) should be fitted in line with the remainder of the buildings fire compartmentation. 74
Fire Stopping The build up of heat and smoke in the area of a fire will be driven through even the smallest of openings It is essential that openings and gaps that breach fire resistant lines are fire stopped to limit fire spread Traditionally done using bricks / mortar, installing fire dampers / shutters in ducting etc. Now also achieved by using intumescent materials to fill gapes or intumescent grills in ducting An intumescent: – A substance which swells as a result of heat exposure, thus increasing in volume, and decreasing in density – Are typically used in passive fire protection especially around doors Protection of Concealed Spaces (Cavities) Large voids can be routes for fire, smoke and gases to spread Fire can spread quickly & go unnoticed until it is too late Compartmentation of concealed spaces and cavities is therefore essential Often achieved by using retardant blankets suspended from the upper face of a void and spanning the entire space – Rock wool mineral fibre is often used for these blankets They produce a fire barrier and thus limits fire spread Rock and Slag Wool Properties: – Excellent thermal insulation – Excellent fire resistance – Excellent sound absorption – Mould, fungi and bacteria resistant 75
Classification of Building Materials The class of a material indicates the speed of surface spread of flame across that material. The classes (Class ‘0’ best) are: – Class 0 (plasterboard, woodwool slabs, mineral fibre board) – Class 1 (wood treated with a fire retardant coating) – Class 2 (pressure treated timber) – Class 3 (chipboard, plywood, hardwood timber) – Class 4 (soft-board, softwood timber) Class 0 is not a true classification, but to be in Class 0 a material must be Class 1 and must not contribute greatly to the propagation of the fire. Sandwich Panels Normally consists of two outer skins of sheet metal (a light alloy) with an infill of heat insulating material (in the past this use to be polyurethane or styrene foam) Use giving rise to great concern: – Buildings constructed of sandwich panels are liable to sudden, unpredictable collapse when a fire occurs – Panels falling out of their framework further accelerate spread of fire – Exposed/heated foam breaks down into volatile flammable toxic gases Fire brigades tend to use a non-attack strategy In recent times they have been used as cladding. Internal Fire Growth & Lining Materials Building boards and slabs classification examples: Plasterboard Class 0 Woodwool slabs Class 0 Class 0 Mineral fibre board Chipboard Class 3 Plywood Class 3 Class 4 Softboard Escape routes and circulation spaces within buildings should have both ceilings and walls comprising materials of Class ‘0’ standard 76
Internal Fire Growth & Lining Materials Wall linings should not be easily ignitable Consideration to be given to potential growth of fire and possibility of flashover Flashover Wall Lining Time Dense non-combustible material e.g. brick 23 mins 30 secs Fibre insulation board with skim of plaster 12 minutes Hardboard with 2 coats of flat oil paint 8 mins 15 secs Non-combustible insulating material 8 minutes External Fire Spread – B4 Requirement, having regard to the height, use and positioning of the building: – The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another – The roof of the building shall adequately resist the spread of fire over the roof and from one building to another. External Fire Spread – Slide 1 Construction of external walls and the separation between buildings can prevent external spread of fire The likelihood of spread depends on: – Size and intensity of the fire in the building concerned – Distance between the buildings – Fire protection given by the facing sides of the buildings Controlling external fire spread – External walls constructed of a material that prevents or reduces the risk of ignition from an external source and the spread of fire over its surface – Unprotected openings limited to reduce risk of thermal radiation affecting an adjacent building – Roof constructed so that risk of spread of flame and/or fire penetration from an external source is limited 77
External Fire Spread – Slide 2 Construction of external walls and roofs: – Structure must be able to withstand effects of fire – Minimum fire resistance for structure elements is 30 minutes and often 60 minutes – Fire resistance requirements can be affected by proximity of adjacent buildings and site boundary. External Fire Spread – Slide 3 Distance between buildings: – Critical distance is 1 metre – less and building regulations will impose various requirements – Amount of unprotected openings in a wall facing another building is another factor An unprotected opening is an opening with a lower fire resistance than the minimum requirement for the wall itself (e.g. a window in a brick wall) Again requirements are greater if distance is less than 1 metre Successful Practical Relevant Means of Escape Element 4.2 78
Means of Escape – B1 Requirement: – The building shall be designed and constructed so that there are appropriate provisions for the early warning of fire, and appropriate means of escape in case of fire from the building to a place of safety outside the building capable of being safely and effectively used at all material times. Means of Escape Definitions/Guidance Means of escape: – Route(s) provided to ensure safe egress from the premises or other location to a place of total safety Place of total safety: – A place away from the premises in which people are at no immediate danger from the effects of fire Guidance: – BS5588 Pt II Fire Precautions in the Design, Construction and Use of Buildings (best practice, but has no legal status) General Principles of Escape There should be alternative means of escape from most situations Where direct escape is not possible, should be able to reach a place of “reasonable safety” Escape routes will often consist of two parts: – The first being the unprotected workplace or accommodation and circulation areas – The second, protected stairways (and some protected corridors) 79
Alternative Routes There is a possibility that a single escape route to a place of safety may become impassable Alternative routes should be provided so people can move away from smoke and flames Sometimes alternative routes not possible and a single route can be accepted as providing reasonable safety dependant on? – Use of building and associated fire risk – Size and height of building – Extent of number of dead ends – Numbers of persons accommodated within the building Maximum Travel Distances Not possible to set maximum distances that would universally apply to travel to the final exit point Codes of practice sets out guidance on reasonable distances for a given situation (next slide) Guidance should only be exceeded if a suitable and sufficient fire risk assessment has determined that a less than average risk can be established. Escape Distances Table 80
Measuring Escape Distances Measuring Escape Distances Escape Times Everyone in the building should be able to get to the nearest place of safety (‘total’ or ‘reasonable safety’) in between 2 and 3 minutes If there is only one means of escape, or where the risk of fire is high, the escape time should only be 1 minute Regardless of the nature of the building the means of escape should be as short as possible The reaction time of people before they begin a fire evacuation should also be taken into account All these points should be considered when carrying out the Fire Risk Assessment 81
Number & Size of Escape Routes Where possible existing means of entrance to and exit from the building should be used These doors should be considered for suitability of location, number and width – If sufficient, additional routes not necessary – If insufficient, further exits should be considered Minimum width of an exit should be 750 mm More than one exit should be provided if more than 60 people are in a room or building Occupancy Calculations Can be simply carried out by checking the numbers using a work area However, possible changes to work area, may vary the occupancy levels Depending on the type of situation there are requirements for empty calculation space per person: Dining room, committee room 1.0 m 2 Offices 6.0 m 2 0.3 m 2 Standing areas in bars Art gallery, dormitory, factory production area, 5.0 m 2 museum or workplace Requirement for Escape Stairs Number: – In general there will be more than one escape stairway – Various considerations will affect the actual number needed Width of escape stairs: – Not less than width of any exits giving access to the stairs – Have a minimum width of 1 metre – Not be too wide so that people spread out during evacuation – Be fitted with a handrail where necessary (dependant on width) – Not reduce in width at any point on the way to the final exit Be suitably protected against fire penetration 82
Doors Prevent the spread of fire and smoke Ensure means of escape for people using the building Should be easily and immediately operable - must not be locked or fastened that they cannot be easily opened by any person who may require to use the exit Should lead to the assembly point Be wide enough to accommodate the number of people expected to use them Emergency doors must open in the direction of the escape Sliding or revolving doors must not be used for exits specifically intended as emergency exits Usually fitted with 3 hinges and positive self-closing mechanism Emergency Lighting Emergency lighting is provided to: – Indicate clearly the escape route – Provide illumination along such routes to allow safe movement towards the means of escape – Ensure fire alarm call points and fire fighting equipment located along the route can be readily located Emergency routes and exits requiring illumination must be provided with emergency lighting of adequate intensity Emergency lighting should be maintained and tested Signage Health & Safety (Signs & Signals) Regs (SSSR) 96 White pictogram on green background (often has supplementary text) Also mandatory signs – white text/pictogram on blue background (can be reversed): Method of sound alarm Method of calling the FRS Method of evacuation Location of assembly point Specific instructions (Do Not Re-Enter) 83
Progressive Horizontal Evacuation Horizontal escape into the adjoining compartments Object to provide a place of ‘reasonable safety’ Further evacuation made if necessary under less pressure of time Integrity of building and fire resistance of compartments needs to be assured for this method Used in hospitals, care homes and other similar premises Maintenance of Means of Escape Management need to ensure means of escape are maintained in an efficient state, good working order and good repair (Article 17) Responsible person must ensure routes and exits are kept clear at all times (Article 14) To achieve this implement: - A of good system of safety checks and inspections - A thorough system of planned maintenance and testing of all aspects of fire safety system 84
Means of Escape for the Disabled Due to Equality Act and requirement to give disabled access to buildings, disabled people may be found in all areas Fire management system should ensure all persons can escape in the event of a fire Responsible person should ensure everyone can escape without the assistance of the FRS Not straightforward - many forms of disability: - Hearing impairment - Vision impairment - Mobility impairment Systems of Escape for the Disabled Horizontal evacuation – covered earlier Evacuation by lift (often used in conjunction with refuges): - Specially designed for evacuation of disabled - Set within a fire resisting enclosure & separate power source Evacuation by stairs: - Most common system is use of ‘Evac+chair’ - Used by trained people - Designed to be used to evacuate down stairs can be adapted for evacuating up stairs Use of refuges: - Relatively safe for short periods of time - Procedures should still provide further evacuation If you cannot get someone out you may need a Refuge 85
Other Way Finding & Exit Sign Systems May be necessary to install additional measures to assist in the evacuation of people with disabilities Such way-finding and exit systems might include: - Graphic - Aural - Tactile Personal Emergency Evacuation Plan (PEEP): - Used where needs of an individual at work are identified and written arrangements put into place to ensure their safe evacuation - Where it is probable that people (e.g. visitors) who will need assistance may be present a similar generic systems can be devised and implemented (GEEP) Successful Practical Relevant Methods and Systems Available to Give Early Warning in Case of Fire, both for Life Safety and Property Protection Element 4.3 Fire Detection and Alarm Systems Opportunity to detect fires at the four stages of a fire? - Invisible products of combustion (e.g. CO detectors) - Visible smoke - Flame - Heat (fixed temperature and rate of rise) Fire detection normally carried out by one of five ways)? - Spot detectors (static detector covering a certain area) - Line detector (linear heat detector cable) - Beam detector (beam of light covering a large floor area) - Sampling detector (pipework connected back to a detector head) - Scanning detector (moving detector sweeping a large area) 86
Categories of Alarms & Detection Systems To summon FRS in early stages of a fire: - Type P1 – Automatic detection installed throughout the building - Type P2 – Automatic detection installed in designated areas Objective to protect people from loss of life or injury: - Type M: Manual System (call points) - Type L5: Life Safety where specific fire engineering solutions or P1 insurance required - Type L4: Life Safety system, as manual + escape route smoke detection - Type L3: Life Safety system, as manual + escape route smoke detection and heat/smoke detection in adjacent rooms - Type L2: Life Safety system; as L3 but detection in fire hazard/risk areas - Type L1: Life Safety, similar to P1 but the audibility is more critical Fire Alarm Zoning Convenient way of dividing up a building to assist locating the fire Zone boundaries are not physical features of building Rules apply to setting up zones: Floor area of single zone not to exceed 2,000 m 2 - Two faults not to leave area of > 10,000 m 2 unprotected - (addressable systems – give unique identification of activation device) If total building area =< 300 m 2 it may be regarded as a single zone - Total building area > 300 m 2 - all zones restricted to a single floor - level Exception to above: stairwells, lift shafts or other vertical shafts - (non-risers) within a single fire compartment should be considered as one or more separate zones The maximum distance travelled in a zone to locate the fire should - not exceed 60 metres Alarm Signalling Used to warn occupants of a fire situation Normally achieved by audible warning devices Must be audible over background noise of area If necessary visual warnings may be used – operation and location of these will be critical Individual vibrating devices may also be used for the impaired Voice sounders followed by a pre-recorded or voice message may also be utilised 87
Single & Two Stage Alarms Single stage alarm: Alarm sounds throughout the whole building Calls for total evacuation Two-stage alarm: Used in certain large/high rise buildings Used to evacuate the high risk areas first – those closet to or immediately above the fire If this is the case, alarm signal to evacuate is given in the high risk area first, with an alert signal to other areas Once the high risk area has been evacuation, if necessary, the alarm signal would sound in the previously alerted areas given them the signal to evacuate Use of Alarm Receiving Centres Permanently manned centres usually provided by a commercial organisation. The centre operators, upon receipt of a fire signal, notify the appropriate FRS The FRS, to help manage false alarms, may require company to register to ensure they comply with certain standards This system currently in use at all MOD sites Manual and Automatic Systems Manual: Simplest system e.g. a hand bell, whistle, air horn Limitations: - Size of building in which it can be heard - Are portable and prone to loss or theft Stand alone call points that operate a local alarm now available Automatic: Covered in earlier slides Call points: Can be used to activate both manual and automatic systems Workers need to be trained how to use them Sited so that they are visible with appropriate signage Max distance to reach call point 30m direct, 45m actual 88
Selection of Detection and Alarm Systems Decision between life risk protection or property risk protection Life risk protection - Type L system - Outcome from fire risk assessment should decide the standard and type of alarm required - Type L1 to L3 are those that are often applied Property risk protection - Type P system - If risk specific to one or two areas Type P2 would suffice - Care to be taken if installing this type to ensure that property risk does not also present a life safety risk Other Considerations Behavioural issues: People not responding to evacuation alarm signals Evacuation delay or not evacuating in an orderly manners Frequent false alarms diminishing creditability of system Practicing and using fire marshals may be used to tackle issues Social behaviour (e.g. night clubs, shops, theatres etc): Linked to behavioural issues Peer pressure and sheep syndrome False alarms: Can cause substantial disruption and burden FRS Regular false alarms result in people disregarding alerts Could be because of: equipment faults, malicious actions and alarms with good intent Requirements for Disabled Persons Standard mounting of call points is 1.4m from floor - May need to be lowered to accommodate wheelchair users Max distance to reach call point same as before, 30m direct, 45m actual - May need to be reduced this if first person to raise the alarm may have a disability that would prevent them getting to the call points easily Other issues already covered in means of escape and alarm systems 89
Successful Practical Relevant Selection Procedures for Basic Fire Extinguishing Methods for Both Life Risk and Process Risk Element 4.4 Types of Fire Extinguisher Water Carbon Dioxide Foam Dry Powder Wet Chemical Types of Fire Extinguisher and How are they identified? There are 5 basic types of fire extinguisher The present scheme being used in the UK are: – Water - red – Carbon Dioxide - red with black – Dry Powder - red with blue – Foam - red with cream – Wet chemical - red with yellow 90
Water Extinguishers Red body Suitable for use on Class A Fires, wood and paper etc. Not suitable for combustible liquids, cooking fats etc. Not safe to use on fires involving electricity Extinguishes by cooling Foam Extinguishers Red Body with Cream label. Suitable for Class A and B Fires. Not suitable for use on fires involving electricity. Extinguishes by cooling and sealing the surface of a burning liquid. Dry Powder Extinguishers Red body with blue label. Best on Class B fires but safe to use on any type of fire. Works by chemically interfering with the combustion reaction. 91
Carbon Dioxide (CO2) Extinguishers Red body with black label. Best on Class B and C fires but safe to use on any type of fire. Safe to use on fires involving electricity. Extinguishes by reducing oxygen levels and cooling. Wet Chemical Extinguishers Red body with yellow label. Best on Class F and A fires. Contains a solution of water and potassium salts which attacks the flame in two ways: The mist cools the fire and lowers the temperature to stop the fire spreading, also prevents splashing of the hot oils/fat. The potassium salts react with the hot oil causing saponification; coating the surface of the cooking oil or fat in soapy foam that is non combustible and acts as a barrier between the fat/oil and the air (oxygen). 92
How do they work? Other Fire Fighting Equipment Hose reels Automatic sprinklers Water spray systems Gas flooding systems Drenchers Fire blankets Siting of Fire Fighting Appliances Portable fire fighting appliances should always be sited: - On the line of the escape route - Near, but not too near, danger points - Near to room exits inside or outside according to occupancy/risk - In multi-storey buildings, at same position on each floor - Where possible in groups forming fire points - Where possible in shallow recesses, if not, sited on a wall - So that no person need travel more than 30 metres to reach a fire extinguisher - With the carrying handle about one meter from the floor to facilitate ease of handling and removal from wall bracket, or on purpose built floor stands - Away from excesses of heat or cold 93
Fire Rating of Extinguishers Fire rating is a way of showing the limits of a fire extinguisher This is only done for Class A and Class B fires Minimum number of Class A (BS 5306 Pt 8) requirements: - Minimum 2 per floor - Total of ratings should be no less than 0.065 x floor area of storey m 2 , but with minimum rating of 26A - Single storey with upper floor area not exceeding 100m 2 a minimum rating of 13A should be sufficient Class B more complicated. Workplace needs to be assessed: - Each room or enclosure to be considered separately - Fire risks more than 20m apart considered separately - Fire risks less than 20m apart can be considered undivided or a divided group Example Fire Ratings of Stored Pressure Fire Extinguishers Model Fire Rating 1 kg ABC Powder 8A : 55B 2 kg ABC Powder 13A : 89B 4 kg ABC Powder 27A : 144B 6 kg ABC Powder 34A : 183B 9 kg ABC Powder 43A : 233B 2 Litre Foam 5A : 34B 6 Litre Foam 13A : 144B 9 Litre Foam 21A : 183B 9 Litre Water 13A 2 Kg CO2 34B 5 Kg CO2 55B Maintenance of Fire Fighting Appliances Given in BS 5306 Pt 3: Monthly inspections : - Located in proper place - If discharged - Correct pressure - Any obvious damage Annual inspection and maintenance : - Thorough inspection of extinguisher - Carried out by a competent person - Spare gas cartridges and replacement charges - May include internal inspection of extinguisher 94
Test by Discharge – How Often? Interval of Extinguisher type discharge Water (stored pressure) Every 5 yrs Water (gas cartridge) Every 5 yrs Foam (all types) Every 5 yrs Powder (gas cartridge) Every 5 yrs Powder (stored pressure valve operated) Every 5 yrs Carbon Dioxide (all types) Every 10 yrs Training in Use of Fire Fighting Appliances RRFSO 2005 does not specify training for fire extinguishers It does require suitable and sufficient instruction and training on the appropriate precautions and actions to be taken Also requires training to be carried out periodically where appropriate If an employee is expected to make use of an extinguisher, this Article confirms that initial training must take place Any person called upon to make use of a fire extinguisher should also be trained in the selection and practical use of the equipment. PUWER (fire extinguishers are an item of work equipment) also requires that users of work equipment are trained in the use of that equipment Successful Practical Relevant Requirements for Ensuring Access for the Fire Service is Provided and Maintained Element 4.5 95
Access and Facilities for the Fire Service – B5 Requirement: – The building shall be designed and constructed so as to provide reasonable facilities to assist firefighters in the protection of life. – Reasonable provision shall be made within the site of the building to enable fire fighters to gain access to the building Access & Facilities for the Fire Service RRFSO Art 38 - in order to safeguard the safety of fire- fighters in the event of a fire, the premises and any facilities have to be are maintained in efficient state, working order and good repair Good sense to provide these regardless of regulations The factors that need to be considered to assist the FRS in their task include: - Vehicle access for fire appliance - Access for fire-fighting personnel - Provision of fire mains (water) in tall buildings - Venting of heat and smoke for basement fires - Fire behaviour where insulating core panels used Vehicle/Fire Fighting Access – Slide 1 Vehicle Access: FRS need to get vehicles as close as possible to buildings to prevent the waste of time running out unnecessary hoses Building regulations lay down minimum access requirements for pumping and high reach appliances 96
Vehicle/Fire Fighting Access – Slide 2 Fire Fighting Access: Low rise buildings, often no additional requirements needed In other buildings additional facilities may be required (fire fighting lifts, stairs and lobbies – normally called fire-fighting shafts) Buildings with floor levels over 18m, or basements more than 10m below, provision to be made for FRS vehicle access and for fire-fighting shafts within the building Vehicle/Fire Fighting Access – Slide 3 Fire Mains (water): Vertical pipe installed with an access point at ground level for FRS Access points also on all floor levels to save a large amount of time/effort running out hoses Buildings having a fire-fighting shaft will also have a fire mains fitted into that shaft Buildings over 60m high will need a wet riser Must be maintained/tested to ensure safe operation when required for use Smoke and Heat Venting of Basements Basements: Notoriously difficult to tackle fires in basements Should have smoke outlets vented to open air so heat and smoke can be released This would then make access for fire-fighters easier May not be necessary for buildings with small basements Fire-fighting shafts also have to be vented Often similar to those used to vent basements 97
Successful Practical Relevant Environmental Impact of Fire Environmental Impact of Fire Not only will the fire damage the premises, but could also affect: – The neighboring properties – The local community – The environment Containment of Water Run Off ~ 1 Sacrificial Areas – Water run off pumped to remote sacrificial area Bunded vehicle parking/other hard standing – Impermeable areas bunded to make temporary lagoons 98
Containment of Water Run Off ~ 2 Pits and Trenches – Subject to potential groundwater contamination, could be used to temporarily hold water run off. Portable Tanks, Overdrums and Tankers – Portable storage facilities, able to be moved and set up rapidly to store water run off or other spillages Sources of Pollution in a Fire ~ 1 Pollutants may escape from site into the water ecosystem by a number of pathways: – Surface water drainage system – Direct run off into nearby watercourses or onto ground with potential risk to ground waters – Via foul drainage system where they could pass unaltered through the sewage system – Through atmospheric deposition, e.g. vapour plumes Sources of Pollution in a Fire ~ 2 Fires can give off large quantities of toxic smoke and fumes which contain pollutants such as asbestos Prevailing winds will carry these over long distances and fall to the ground in rain water 99
Toxic and Corrosive Smoke Smoke consists of small particles or partially burnt carbonaceous materials The size and quantity of particles will determine the thickness of the smoke which can be further thickened by water vapour Smoke and its by products are normally very corrosive and can cause long term damage to buildings and other materials if not cleaned correctly Liaison with External Agencies In order for emergency plans operate smoothly and efficiently, it is important that responsibilities are set down and understood both internally and externally. External agencies that could include those that may be involved in the development of plans as well as its implementation. The FRS and EA will work together in the event of a fire to minimise the environmental impact. Successful Practical Relevant Relevant Statutory Provisions and Guidance 100
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