The Australian Library Journal
volume 50 issue 2

Mould: the invasive intruder!

Being situated in the north tropics of Australia is an experience in itself, for someone who has never lived in this environment it is a daunting experience to realise your collection is now growing mould. When the collection is a valuable research collection used by research scientists in their quest for knowledge and understanding of the marine environment, you have to take immediate action. How we combated the invasive intruder is documented here with some basic recommendations and things to be aware of when checking your collection. Beware! It could happen to you.

Manuscript received August 2000

The library is an open floor plan design with no internal walls and two floors. An atrium is situated in the middle of the library giving an open and spacious feeling. The 10 000-volume book collection is housed on the ground floor and the periodical collection (1500 titles) is housed on the first floor.

During the wet season of 1999 we experienced a major mould problem. The tropical levels of humidity increase the rate of organic deterioration of paper by the acids used in its manufacture and also increase the risk of mould. Air conditioning is commonly used to control these conditions with an optimum temperature of 21°C and relative humidity at fifty per cent: unfortunately due to a number of unavoidable malfunctions, our air conditioning unit failed and levels of humidity reached eighty per cent. Within days the collection was exhibiting isolated occurrences of mould and it was spreading rapidly.

First signs
Early in March 1999, after a long weekend, as the first people entered the building it was noted that the smell of mould was extremely strong. Examination of the collection identified a film of mould spreading across it. The first signs of mould were found on blue-coloured volumes which according to the consultant we later used are apparently more susceptible to or revealing of mould growth than other coloured volumes.

The first books identified with mould were housed in an open corridor where sliding doors provide entry to the building. Further examination of the area revealed that a number of seals around the library balcony windows were deteriorating and were leaking. It was also noted that the building itself was extremely hot. Temperature and humidity readings were taken: it was found that humidity was at eighty per cent plus and it was clear that it had been like this for an unknown period. Not being familiar with processes for dealing with mould I asked the librarian to check with some authoritative sources on how to combat the situation. The librarian rang the State Library of Queensland, James Cook University and the National Library of Australia. As we are very isolated, and at great distance from all of these institutions it was difficult to establish a clear and concise definition of the problem over the telephone except to say that the mould was growing. At this stage not all the variables of the air conditioning unit were yet identified. We also contacted our network friends from IAMSLIC (International Marine and Science Libraries and Information Centres) and the FISHNET group via e-mail.

We received a variety of differing views on how to handle the problem:

• Use a biocide through the aircon every few months, and to thoroughly clean the whole collection and shelves using a Hepa filter vacuum cleaner that would prevent redistribution of spores.
• Get fans circulating the air; be sure maintenance cleans the filters in the air handling system after fixing the air conditioning units or it will just continue to grow and spread all over your library again. Also buy some dehumidifiers and keep them going. That's the best way to keep them [sic] bugs away.
• First off, you need to be wiping your books with rubbing alcohol only. Do not dilute it with water. Your problem is caused by moisture, and mixing water into your cleaning solution only makes matters worse.
• The first thing to do is get your humidity way down. We put in a new dehumidifier and ran two fans day and night to dry everything. We also wiped off all the books and shelves with sponges used to reduce dog odor and clean smoked walls (don't ask me what they have in them, but it works).
• I was given certain instructions for mould cleaning. They came from a conservation/preservation librarian from main campus and she had me wipe each book (using handi-wipes) with LYSOL disinfectant spray only. Wipe not only the outside covers but generally open the covers and catch the inside edges as well. Be careful about using 'water' to wipe the books, even though the mixture is part ethanol. You don't want to add more moisture to them. Our shelves were cleaned with a mixture of liquid LYSOL and water.
• We turned up the air conditioner (68 degrees F.) and added a dehumidifier. We used Lysol brand disinfectant on the books and journal as well as the mixture you are using. Controlling the humidity has helped the most.
• I used a hospital disinfectant deodorant called Zepynamic. This stuff kills everything ... a broad-spectrum disinfectant and antimicrobial agent, virucidal, tuberculocidal, fungicidal, bactericidal, pseudomonicidal, staphylocidal, sanitizes fabric and leather, controls mould/mildew fungi. I have not been able to control humidity or temperature levels and after using this stuff, I have had no mould/mildew come back! Temperature and relative humidity have to be monitored constantly. Reduce temperature to below 68 degrees F and humidity to below fifty-five per cent if possible.
• Mould threshold is sixty per cent humidity or higher. Once mould is in the collection, and in particular in the book's 'block', it cannot be eradicated...only kept in check. Once mould is arrested on the infected material with chemicals, you keep mould in check by having less than sixty per cent humidity and good air circulation. If humidity threshold is reached, the mould returns and spreads. It is important that infected books be handled carefully to avoid contaminating other material.

I also received a number of internet site addresses that provided information, but at this point I just wanted to know what to do now and with the helpful advice received, my librarian and myself sat down and worked on a plan to combat the situation.

Plan of action
We discussed the situation with our manager, supply and property, who is responsible for ensuring that the air conditioning unit was functioning. He had organised for the air conditioning suppliers to come and check the system over and to identify what might be done immediately. A number of technical problems associated with the unit were identified. These problems were dealt with as they were identified and located by our maintenance personnel and we focussed on lowering the humidity as quickly as possible. It is understood that the failure of the air conditioning unit was the prime cause of the outbreak.

Immediate action
We then asked our fungicide chemists what they thought would be the best solution for dealing with the immediate problem. Again we did not get consensus, and we needed to be mindful of the effects of using materials or chemicals that could be harmful to staff. Between us we decided to use a mixture of eighty per cent ethanol, ten per cent fungicide (Nystatin and cyclohexamide) and ten per cent water to clean the books and shelves. We issued a warning to all staff to remain away from the area if they were suffering from any respiratory problems.

Because our organisation is a research organisation we were able to obtain from our stores large quantities of Ethanol, rubber gloves, masks and cleaning wipes. Assistance was provided by our cleaning services and with the librarian and myself, a total of six, we began cleaning the books. We provided instruction and equipment to the cleaning services. We found that this process was particularly tedious and very labour-intensive. By the end of the day we had only cleaned one quarter of our book collection.

When we arrived at work the next day we found that the mould had increased and had spread at an alarming rate further into the collection. I discussed the rapid spread of mould with the Institute's management and it was agreed that the director would issue a general call to all staff for assistance. We set up a roster to manage the staff and cleaning operation. Any staff member who came to assist was issued with rubber gloves, a mask and a fungi solution. Each was instructed to use the safety equipment and given instruction on how to clean the books, the librarian was in charge of making the ethanol mixture.

The process included the following steps:

• remove the books from each shelf;
• clean the shelf with the mixture;
• clean each book's outside covers, inside covers and all spines and edges; and
• place books back on shelf in order.

During the afternoon of the second day the whole air conditioning unit fused and we lost all air conditioning for the rest of the day until about 4:30pm. We decided that we could do nothing more that day.

Third day
The situation had become catastrophic with the spread of mould now making its appearance in our periodical collection on the first floor. We thought that it had been contained on the first floor and our book collection. We diverted staff to the first floor and began an intensive cleaning operation of the periodical collection, much of which is not bound. This required the disposal and replacement of many periodical boxes, just to add to the confusion. By the third afternoon we had located a service that guaranteed to clear the mould within days. Because everyone in the institute had been at some stage involved in the cleaning process they had experienced at first-hand the labour intensiveness of the process and were therefore happy with the decision to have a service come in and fix the problem.

The final solution
A Brisbane-based company, Moisture Control Services, was identified and contacted and I gave them a description of our situation and of our current actions and we agreed that, although the process would not be a permanent solution, it would at least temporarily contain the spread of the mould. To ensure that our staff, laboratories and specimens would not be harmed by their process Moisture Control Services agreed to send information on the process and chemicals they would use to clear the mould so that we could ascertain its safety and effectiveness. We received the MSD (Material Safety Data) sheets within the hour and checked with our scientific staff about its possible affect on their work environments. The substance to be used was considered to be harmless in our work/laboratory environment. The cost, in relation to the value of our library collection options, considered acceptable.

Moisture Control arrived on Saturday morning and we showed them the library, at the same time discussing what they would do and how it would be done. They would use what they called a 'fogging machine', which actually sprays a very thin mist over the books and the floors. The operator wears protective clothing and the fogging machine is strapped on the back like a knapsack spray so that the operator has complete flexibility. We tested the process on some sample items that could, if necessary, be sacrificed. Within one hour of spraying the mist on the sample books the mould had completely disappeared. We agreed to proceed.

The ground floor was completed by mid-afternoon. This included spraying all the books, shelves, floors and library offices. The next area was the basement where the operator sprayed the air conditioning chambers. Once this had been completed the operator began the first floor periodical collection. This floor was completed the next morning and by 2:00pm the operator was packing up and ready to leave. Overall the process took about twelve hours and was very efficient. By Monday when staff returned to the Institute the only lingering evidence of the process was a citrus smell coming through the air conditioning units. We have since been through another wet season and I am happy to say that we have not had any further problems.

Recommendations
I have listed here some of the recommendations made to management.

• It is imperative that the air conditioning unit gives us maximum control of the environment. The optimum humidity level for a library is fifty-five per cent or less humidity. It would be prudent to ensure that the system be upgraded to maintain this level.
• If the air conditioning unit cannot stabilise the humidity and temperature throughout the library, dehumidifiers should be purchased (or rented) and placed strategically around the library environment to ensure environmental control is maintained.
• Constant monitoring of the humidity should be carried out. It is recommended that the relevant instruments be purchased to ensure that this can be done efficiently.
• External doors to be kept closed.
• That materials required to contain any future mould outbreaks are kept in stock.
• Indoor plants should be kept to a minimum in the library.
• Gutters (especially on library balcony) to be made more effective so that water does not collect near the outside walls and windows.
• Seals around the library balcony windows to be monitored and replaced as soon as they start to deteriorate.

I would like to take this opportunity to thank those many people who initially responded to our cries for help especially our librarian Carolyn Kenny for her tireless efforts to contain the problem. I was totally unprepared for this eventuality, as I had not lived in the tropics before; and neither of us had had any experience in dealing with mould. We learnt most of all to be ever vigilant.

References
National Library of Australia, 'PRESERconVersATION: Mould, mildew and library books' http://www.nla.gov.au/pres/conver/100196.html

Northeast Document Conservation Center 'Emergency salvage of moldy books and paper' by Beth Lindblom Patkus http://www.nedcc.org/plam3/tleaf39.htm

The NEDCC also has a great preservation manual: http://www.nedcc.org/plam3/manhome.htm

Kovacic, ES and Sturman-Wolfson, LS 'Moldbusters!!', CAN No. 50:6-7,28

SOLINET Preservation Services. 'The invasion of the giant spore.' http://palimpsest.stanford.edu/solinet/moldnew.htm

SOLINET Preservation Leaflet #5. Atlanta: SOLINET, January 1997.

Wellheiser, JG Nonchemical treatment processes for disinfection of insects and fungi in library collections. London, KG Saur, 1992. (IFLA publications 60)

Weaver-Meyers, PL, Stolt WA and Kowaleski, B 'Controlling mould on library materials with Chlorine Dioxide: an eight year case study.' In: Journal of Academic Librarianship 24 pp455-458.

Wilson, WK Environmental guidelines for the storage of paper records. A technical report sponsored by the National Information Standards Organisation. NISO Technical Report No. 1 NISO TR01-1995 ISSN 1081-8006

Balcony windows with leaking seals

Sliding door entrance

Blue books showing first signs of mould growth

Mould growing on books