Effective Use of Two Stage Alarms & Voice Communication Systems Approving These in Fire Safety Plans Sean Tracey, P.Eng., MIFireE Canadian Regional Director NFPA
Outline of the Presentation • Background • Overview of Fire Alarm Provisions • Code provisions for voice systems • Code provisions for voice systems • Advantages • Hurdles • Fire Safety Plan Considerations • Resources
Background • Why begin to look at this? • National Capital Region issues • National Capital Region issues • The selection and effective use of alarm and comms systems has an impact on fire ground operations
World Trade Center Disaster September 11 th , 2001 • NFPA only Standards Developer on initial BPAT • Recommended changes from NIST studies being forwarded through TCs • NFPA forms High Rise Advisory Council
Chicago Fire October 17 th , 2003 • Around 5 pm • Storage closet on the 12 th floor • 6 fatalities • 6 fatalities • Major recommendations regarding sprinklering, employee training, and fire department operations
Fire Alarm Systems • Purpose of a fire alarm system – Notify occupants of a fire – Signal indicating an emergency – Signal indicating an emergency – Occupants to start required evacuation – On activating give sufficient time for evacuation.
Code Requirements • Note: NFPA has different terminology including general evacuation alarm, private mode and pre-signal mode
Fire Alarm Systems One Stage vs. Two Stage • Single stage: upon the operation of any manual station, waterflow detecting device, or fire detector , cause an alarm signal to or fire detector , cause an alarm signal to sound on all audible signal devices in the system
Fire Alarm Systems One Stage vs. Two Stage Two stage: a) alert signal upon the operation of any manual station, waterflow detecting device, or fire detector, b) Automatic alarm if not acknowledged within 5 min of its initiation, and c) have manual stations, that causes an alarm signal to sound Allows supervisory staff to investigate as well can allow for zoning
3.2.4.3. Types of Fire Alarm Systems A single-stage system in a Group F, Division 1 occupancy , A 2-stage system in a Group B occupancy , A single- or 2-stage system in a Group B, A single- or 2-stage system in a Group B, Division 3 occupancy where the building is 3 storeys or less, and A single- or 2-stage system in all other cases. Technically you can have a single stage fire alarm system in a high-rise office tower or hotel. Should this impact the design of means of egress and fire safety plans?
Fire Alarm Systems One Stage vs. Two Stage • Two-stage alarm systems are normally used if programmed evacuation is required or if a general alarm would cause undue distress to general alarm would cause undue distress to the occupants, for example in health care facilities. – Reduces the potential for false alarms – In high buildings this can facilitate the staged evacuation and thus reduce the impact of the evacuation on the means of egress
Voice Communications Systems NBC 3.2.6.8. High Buildings A voice communication system conforming to Article 3.2.4.22. shall be provided in a building if building if a) the floor of the top storey is more than 36 m above grade , or b) a floor area or part of a floor area located above the third storey is designed or intended for use as a Group B, Division 2 or 3 occupancy .
Voice Communications Systems • NBC also requires those with more than 1000 occupants and having a two stage alarm system to have voice communication alarm system to have voice communication systems to facilitate in the evacuation and messaging to the occupants. • To operate the alarm system the facility is required to establish a control facility [3.2.6.7]
Comms Centre Requirements • a) a two-way means of communication with the central alarm and control facility and to the mechanical control centre from each floor area , and • b) intelligible loudspeakers operated from the central alarm and control facility
The Problem • Code may require a two stage alarm system but the NFC does not mandate that this be used used • This can result in inconsistent application within a jurisdiction – impacts operations! • The best solution is to have consistent requirements when approving fire safety plans
Supervisory Staff and Voice Comms Elements in the FSP • The training of supervisory staff in the use of the voice communication system, • The the action to be taken by supervisory • The the action to be taken by supervisory staff in initiating any fire emergency systems until the fire department arrives, • Instructions to the supervisory staff and fire department for the operation of the systems referred to in Clause (c), and
Problem with Supervisory Staff Training, and Availability • The problem is that supervisory staff may not be adequately trained on how to use the system and may not be confident in its use. system and may not be confident in its use. – Property Owners let these go to alarm – Impacts the credibility of the alarm system • What happens when supervisory staff are not available or after hours? – System goes to alarm
Fire Safety Messaging by Supervisory Staff • Intelligible pre-recorded, synthesized, or live messages • shall be designed so that the alarm signal in • shall be designed so that the alarm signal in a 2-stage fire alarm system can be selectively transmitted to any zone or zones while maintaining an alert signal or selectively transmitting voice instructions to any other zone or zones in the building
Human Behaviour During Fire • Confidence in Emergency Procedures - clear concise messaging by supervisory staff ensures that the building occupants staff ensures that the building occupants have confidence in the overall alarm system • Voice Communications – are proven reinforcing queues* -- reduces alarm recognition time
Evacuating People with Disabilities • Fire Safety Plan should identify if this is an issue and the procedures to follow • Are there adequate features to allow defence in areas of refuge? defence in areas of refuge?
Types of Evacuations • Total • Total –staged • Partial • Relocation –Horizontal –Vertical
Total Evacuation ALARM ALARM Single stage evacuation of a building
Staged Evacuation ALARM ALARM Found with 2 stage alarms – alarm sent to the fire floor and remaining floors in alert notification.
Horizontal Relocation
Relocation ALARM ALARM Relocation Area Relocation Area Two stage alarm - notification of fire floor remainder of building in alert stage.
USFA Special Report Operational Considerations for Highrise Firefighting, April 1996, In some cases, occupants may be safest if they remain in place or evacuate to a floor beneath the fire floor instead of exiting the building. Firefighters should determine as quickly as possible in a fire incident whether a full, partial, or no evacuation is necessary, and communicate their evacuation plan to occupants by using a public address system or other means. Experience shows that occupants will need guidance with evacuation. Waiting until the incident to determine the evacuation plan is too late. Needs to be part of the pre-incident plan and therefore Fire Safety Plan.
Which Type of Evacuation? Determined in the FSP for the facility by the property owner • Occupancy type – but this selection impacts • Risks present FD Ops. • Occupant issues • Building size (both height and footprint) • Building layout – presence of zones • Building construction • Protective features & alarm systems
Means of Egress Capacity & Occupancy Load Module 3- 28 Module 3-28
An example of queuing. Photo taken by John Labriola during WTC evacuations.
An example of cross flow. Photo taken by John Labriola during WTC evacuations.
FD Operations • Impact on operations – Cross flow – Can’t commence stairwell attack – Staging of apparatus • Fire service is expected to take over voice comms on arrival • SOPs needed when two stage alarm systems are present with voice comms
FD Operations • No consistent standards or procedures adopted for this • Need procedures on how they will direct occupants to evacuate. occupants to evacuate. • Has a direct impact on FD considerations • Pre-Incident plans reflect what expectations are of building owners • SOPs needed to clarify this so building owners will understand their responsibilities
Advantages of Effective Alarm System to Tenants/Occupants • Greater confidence in systems • Potential for injury is reduced • Lessens the impact of false alarms on • Lessens the impact of false alarms on workplace productivity
Advantages of an Effective Alarm System to Fire Services • Proven better managed evacuations • More effective fire ground operations – Reduces the potential for cross flow – Reduces the potential for cross flow – Quicker setup in stairwell • Smoother transition to take over of facility communications
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