INFS 423 Preservation of Information Resources Lecture 6 – Deterioration Caused by Biological Agents (Deterioration Caused by Fungi) Lecturer: Prof. Harry Akussah & Mr. Michael Allotey , Contact Information: mallotey@ug.edu.gh, hakussah@ug.edu.gh College of Education School of Continuing and Distance Education 2015/2016 – 2017/2018
Lecture Overview • In this Lecture, I am going to continue discussing with you agents in the environment that cause biological degradation of documents. I will introduce you to such agents as fungi, insects and rodents, pressing home to you how dangerous they can be to our information resources. This Lecture is very crucial, given the fact that these agents abound in most environments. I will implore you to relax, concentrate and make the most out of this unit. • The lecture will focus on deterioration documents caused by Fungi by introducing you to the damages caused by fungi to information resources. I will lead you into how to identify the fungi infestations, the damages they cause, how to prevent the infestation and how to treat the infestation if it does occur. This lecture promises to be an interesting one since most of the discussions relate to things we see and experience even in our homes. Slide 2
Lecture Outline The key topics to be covered in the lecture are as follows: • Defining Biological Deterioration • Categories of Agents Responsible for Biological Deterioration • Deterioration by Micro Organisms • Damages Caused by Fungi Infestation • Control of Fungi Infestation Slide 3
Reading List • Akussah, H. (2011). Preservation of Documents. Department of Information Studies, Legon, NAB Superior Services. • Gorman, G. E., & Shep, S. J. (2006). Preservation management for libraries, archives and museums. London: Facet Pub. Slide 4
Topic One DEFINING BIOLOGICAL DETERIORATION Slide 5
What is Biological Deterioration Degradation of documentary materials resulting from activities of living organisms. Slide 6
Topic Two CATEGORIES OF AGENTS RESPONSIBLE FOR BIOLOGICAL DETERIORATION Slide 7
Categories of Organisms • Micro-organisms • Fungi • Macro-organisms • Insects • Rodents Slide 8
Topic Three DETERIORATION BY MICRO- ORGANISMS Slide 9
Deterioration by Micro-Organisms • Types affecting documents – Mold and Mildew (These are two common forms of Fungi) • Propagation – Through Spores :These spores or seeds are numerous and subsist on organic matter. Slide 10
Fungi Spores or Seeds • The spores or seeds that cause mould to grow are present in the atmosphere and can never be eliminated completely from the environment. Mould needs nutrients to grow, such as paper, leather, glues and adhesives. As access to these nutrients cannot be restricted, the growth must be inhibited by controlling the environment. • The spores remain dormant or latent in their dry state but they begin propagation when environmental conditions are favorable. Slide 11
Favourable Condition for Spores • Warm and humid condition – Temperature above 24C – Relative Humidity above 65% • Continuous period of darkness • Little or no circulation of air • Pockets of stagnant air • Previously poorly treated infestation Slide 12
Symptoms of Infestation • Musty odour, Yellowish, greenish or/and brownish spots, Particularly on the spine of documents. • This is because they are attracted to starchy materials which hold the document together and this can be found at the spine. Slide 13
Activity 1 • Make a study visit to any public library, archives or records centre. Inspect critically the storage area for evidence of fungi infestation. Explain in 200 words, the possible reasons for the infestation Slide 14
Topic Four DAMAGES CAUSED BY FUNGI INFESTATION Slide 15
Damages Caused by Fungi Infestation • Fungi feed on the following: – Cellulose – Starch – Adhesives – Sizing Materials These result in the weakening of the documentary materials leading to their ultimate breakdown. • They stain documents – Temporarily – Permanently (Foxing – small brown dots) • Finally Fungi are dangerous to custodians and patrons (they can cause diarrhea). Slide 16
Damages Caused by Fungi Infestation Foxing are rust-brown measles-like spots that are frequently found on paper and in older books and prints. Foxing is evidence that fungi have been at work, but they are no longer active. Foxing stains can only be removed by bleaching: a part of hazardous operation which can easily damage the entire book if not expertly done. Foxing is therefore an unpleasantness best ignored. Slide 17
Topic Five CONTROL OF FUNGI INFESTATION- PREVENTIVE & CURATIVE MEASURES Slide 18
Preventive Measures The best prevention however is to practice good housekeeping procedures. In addition to this a number of steps can be taken: • By monitoring collections to identify problems in the early stages before they worsen. • Records should be stored in areas where there is free circulation of air. Temperature and relative humidity should be controlled as close to ideal levels as possible. • While it is best to limit light levels, some lights should be kept on in environments with high relative humidity. In this instance, light can dry out the air, somewhat reducing relative humidity and inhibiting mould growth. Slide 19
Preventive Measures • Documents should not be shelved too tightly. • Water leakage should be avoided within or around the immediate vicinity of the storage area. • Wooden furniture and heavy cotton curtains should be used for the storage area. Slide 20
Curative Measures Infestation may be at two levels. • Localized infestation – This is where a few materials in the storage area are infested. For instance part of a shelf or selected areas within the storage area. • Universal infestation – With this type of infestation, almost all documents and resources are infested including the shelves, tables, chairs and documentary materials. Slide 21
Curative Measures • Whatever the level of infestation; Fumigation using fungicide is the solution. This is a process of exposing infested documents and records to a toxic chemical, in gaseous form, to kill the mould. • It is a controversial process, as the chemicals used can sometimes damage the documentary materials themselves or may be harmful to humans. • Examples of Fungicides: – Formaldehyde or Formalin – Thymol – Acetone – santrobite. Slide 22
Curative Measures • For universal infestation however, the appropriate action to take is to convert the entire storage area into a fumigation chamber making sure a hermetical environment is created by closing all windows and blocking all holes through which air can enter. Fungicide is then injected and the place is sealed for as long as required. • For universal treatment, it is advisable to use fungicides of low toxicity which are not water-based but solvent- based, in order not to stain the documents and this must be done by a professional. Slide 23
Considerations • Look for fungicide with low toxicity. • Look for those with little harmful effects. • Consider cost and availability. • Always seek expert assistance to determine extent of attack and prescription of appropriate fungicide. Slide 24
Activity 2 • Following from activity 1 write down four (4) steps you think the information centre should take reduce damage and to prevent subsequent infestation. Slide 25
Summary What a joy to have been able to complete this Session. You have become conversant with the following: • Symptoms of fungi infestation • Damages caused by fungi infestation • How to prevent fungi infestation • How to treat fungi infestation. Slide 26
Recommend
More recommend
