Staff Papers

A Vacuum Freeze Drier: It's Nice to Have One But ... A Short Paper on the National Library's Vacuum Freeze Drier Nine Years On

Paper by Kim Morris, Preservation Services on the National Library's Freeze Drier, nine years on.


The National Library of Australia was among the first Australian cultural institutions to investigate vacuum freeze drying technology as a disaster recovery measure. It recognised a need for local expertise to be developed in this area and purchased a vacuum freeze drier in 1986.

Since then research and development and then several private drying projects have seen the equipment used for only about one third of its life. With cost effectiveness a prime Government objective in the 1990s and changing work priorities there is pressure on Federal and State cultural institutions to re assess their involvement with low use equipment.

The paper reviews the history of the National Library's vacuum freeze drier and discusses factors which may influence the Library's future direction in this area.

CONTENTS


Introduction

Is it appropriate for a major cultural institution like a national or state library to own a vacuum freeze drier or not? This question has been asked many times over the past ten years in Australia. Institutions have had to weigh up affordability against cost recovery and the prospect that the equipment will rarely be used. Most have, justifiably, decided against purchasing one. Investing in expensive equipment like a vacuum freeze drier can be compared to keeping an insurance policy, a necessary expense to acquire and maintain protection. However, when we (fortunately) have no disasters and the equipment lays idle we are tempted to re-assess the cost just as we do whenever we receive an insurance renewal notice.

This paper relates the National Library's experience with its vacuum freeze drier over the past nine years and discusses our view of the future direction of this technology in Australia.

The views expressed are those of the author and not necessarily those of Preservation Services or the National Library of Australia.

The National Library's Vacuum Freeze Drier

In the mid 1980s there were few large vacuum freeze driers in Australia. Following the 1985 fire, the National Library made the bold decision to purchase its own vacuum freeze drier as part of a major upgrade of disaster prevention and preparedness contingencies. In October 1986 the Library took delivery of the unit.

In deciding on this course the Library considered a number of factors:

  • the extremely limited availability of large vacuum freeze driers in Australia. In the mid 1980s there were few such units readily available for disaster use by cultural institutions . Small units were being operated by some food processing and pharmaceutical companies though most companies still used overseas vacuum freeze drying facilities.
  • limited availability of skilled technicians. At that time virtually no people in Australia had experience in treatment of water damaged paper based collection materials using vacuum freeze drier technology. Large, well established, United States based disaster recovery companies were apparently prepared to come to Australia should the situation arise, however this has never been tested. The National Library of Australia recognised this gap and undertook to develop local skills.
  • the realisation that a major catastrophe could happen to a large cultural institution like the National library of Australia. Following its fire where a large amount of material was wet and/ or soot affected, disaster planning for Australian cultural institutions received a large amount of attention and resources. Preventive and preparedness plans were developed. The prospect of coping with future large disasters using vacuum freeze drier technology appeared very attractive, less damaging and more easily managed compared to huge air drying exercises.

The Equipment

The National Library's vacuum freeze drier unit is a Dynavac FD 1000 with a 1m x 2m chamber with four flat temperature controlled shelves, essential for removing ice blocks from the centre of wet frozen books. This size was large by Australian standards at this time. However later experience has proven it to be too small to be an effective option when dealing with large amounts of wet material due to the time factor. Larger 2.5m x 5m chambers were available but cost and accommodation problems ruled these out. The unit was delivered in parts and assembled on site by Dynavac technicians. It was commissioned in February 1987.

Eight Years In Review

Initial Testing

To familiarise ourselves with the unit and determine the best drying process a testing program was developed. This involved drying four groups of wet and frozen books: hard covered volumes in a milk crate, soft covered volumes in cardboard boxes, large hard covered books with plastic covers and odd sized books placed directly on the shelves. This testing and development program was initially cut short by mechanical failure in the vacuum pump and then the compressor.

Results from these tests showed the unit was capable of drying a moderate load averaging two hundred very wet books in two weeks with the assistance of the heated shelves in the second week. Interesting observations were that non interleaved books separated just as well as interleaved books and the relative position of material in the chamber had a marked effect on their drying rate. Type of container and covering marginally affected the drying rate. Perforated cardboard boxes were more effective than non perforated but similar to milk crates.

Variations on this type of testing were carried out through 1987 and 1988 and enabled staff to become fully familiar with the FD 1000's Service requirements, idiosyncrasies, abilities and limitations.

Cost Recovery?

In the late 1980's the words "cost recovery" began to ring in the ears of large Australian cultural institutions. Managers were asked to identify potential revenue raising strategies. The National Library's vacuum freeze drier was an obvious possibility as through good disaster planning and a little luck it had only ever been used for testing and was idle at all other times. Prior to purchasing the unit other institutions had expressed interest in using it should the necessity arise. Researchers from private industry had also contacted the Library with proposals to use it for vacuum freeze drying such things as flowers, deer antlers and glutens.

Dynavac and the Australian Valuation Office were contacted to assist in determining an appropriate rate. Based on the value of the unit, running costs, the supply of an experienced technician and CPI, a fee of between $A400 and $A500 per day was recommended. This figure was much higher than expected and very expensive, even by today's standards considering a vacuum freeze drier runs twenty four hours a day, seven days a week. No client has yet agreed to pay this price.

Into Action

In 1989, after a small project to dry glutens, a Victorian conservation consultant approached the Library with a proposal to lease the unit and work space to vacuum freeze dry and treat fifteen pallets of material damaged when water flooded his client's basement. The client's insurance company had agreed to consider covering the cost of recovery rather than writing the material off. It became quickly evident that the Library's daily fee was way above what the market was prepared to pay.

Long and protracted negotiations took place and eventually a twelve month licence fee for $A1,300 per month was signed. Briefly, the agreement involved the Library providing the equipment, space, technical advice and servicing and the consultant employing a person to run the project. The Library retained the right to use the vacuum freeze drier should the need arise.

You don't have to be a genius to calculate that the agreed fee was dramatically lower than that recommended. For the National Library the choice was simple: allow the vacuum freeze drier to lay idle, making no revenue at all or accept what was offered and derive positive feed back from the largest vacuum freeze drying project for wet material Australia had seen. The choice was made even easier when it was considered that this type of equipment cannot be allowed to be idle for too long. The vacuum pump must be run regularly to prevent damage and the machine needs regular maintenance to ensure all components operating correctly.

The project commenced in 1990 and took thirteen months to complete. Allowing for down time for servicing and repair it took an average of twenty nine days per load with the chamber packed to capacity to process the material. I quote these figures only to illustrate the time it takes to process a large amount of material through a unit of this size. A large project is therefore a very expensive exercise and has the added cost of freezer storage for the duration of the project.

Two other major vacuum freeze drying projects have been carried out using the National Library's facilities, both involving fire damaged wet material. The first was completed by a private conservation consultant in 1991 and took three months. The material was less wet than the previous major project and shorter drying times per load reflected this.

The second involved one pallet load of heavily fire damaged manuscript material, privately owned, but of great cultural significance. The National Library was approached by another library in 1993 to vacuum freeze dry the collection in a cooperative cost sharing project over three months. The project was completed after significant down time when the vacuum pump required major rebuilding.

Since this time the vacuum freeze drier has remained unused except for regular maintenance running and servicing.

The Current State of Play

Since those heady, pioneering days in the mid 1980s disaster preparedness and response in Australian cultural institutions has come a long way. Most have well developed plans and are capable of coping with the common types of incidents. Thankfully, we are yet to suffer an absolute catastrophe although many smaller disasters have occurred. As long as we remain committed to revision and maintenance of our plans we can be satisfied with our progress.

Australian vacuum freeze drying resources have steadily increased to the stage that it is now possible to contract specialised and well resourced disaster recovery companies to carry out Vacuum freeze drying. Whether they succeed in business, time will tell.

Many small cultural institutions, from the local museum through to libraries and galleries remain uninsured and are not indemnified by government. When they experience a major disaster they are restricted by cost to either lose material or manually treat them the best way possible. Vacuum freeze drier technology is out of the question for this category unless funding can be found or an institution like the National Library donates its resources. There have been a number of small collections in freezers around the country waiting for such help and cooperation in recent years.

It appears that cost and the time frame of such projects have kept most prospective clients from using the National Library's vacuum freeze drier facility in recent years. Most have preferred to air dry wet material risking damage and mould growth or to dispose of it rather than taking the labour intensive route of prioritising, freezing, finding funding and gradually treating it.

Where To Now?

The Library is now faced with a some choices. Points for consideration include:

Can we justify the resources to maintain the equipment in top running order and technical skills waiting for the call to action? At least one staff member has to know the equipment intimately to be able to recognise problems and appropriately treat material. It is very easy to lose most of the knowledge developed since the beginning due to staff turnovers, current work priorities and increasing demands in other areas.

There are now other options open to the National Library if vacuum freeze drying of its collection material becomes necessary. Contractors with large capacity and technical expertise are now available in Australia.

Knowledge and expertise developed over the last nine years has proven invaluable for dealing with large amounts of water damaged library material. This research contribution has justified our original decision to purchase and perfect the vacuum freeze drier.

Has the vacuum freeze drier been of much use to the National Library in a real sense, ie: dried any of our collection material? The answer, fortunately, is no. While we have had our share of minor disasters over the last nine years none have required use of the drier.

Do we see a continuing vacuum freeze drier program for the Library? You never know. That old insurance sales pitch is a solid argument for retaining our equipment and expertise. Pipes may burst, dams may break, roofs may leak. The vacuum freeze continues to be a major part of our "insurance policy".

Provided we have appropriately prioritised our collections we believe the Federal Government would indemnify our recovery costs. Therefore we may be well able to use contract facilities.

Is there a place for the National Library's vacuum freeze drier in the Australian disaster recovery community? Most definitely! It is available for use by other cultural institutions and private companies at any time. The Library sees its drier as part of the growing inventory of this type of equipment in Australia which, when grouped together, would provide a rapid and cost effective service.

Conclusion

The National Library's Dynavac FD 1000 has clocked up approximately two and a half years running time in its testing and development and drying projects since its commission in 1987. Staff have acquired expertise in vacuum freeze drying a wide range of paper based materials varying from items with little damage through to badly fire damaged. However it is now time to re assess the situation by weighing up the benefits against the cost.

In many ways we have had a love/hate relationship with our vacuum freeze drier. On one hand it has proven to be of great benefit to at least three important collections over the years. On the other its future use depends on fate. Disasters will happen, but when. Can we afford to maintain an expensive piece of equipment and a high level of expertise with that degree of uncertainty?

The time for reappraisal is nearing.


Author Autobiography

Kim Morris is a paper conservator working as Collection Preservation Laboratory Manager in Preservation Services at the National Library of Australia. He has worked in the conservation field for the past twelve years, mostly in cultural institutions based in Canberra. In recent years he has been involved in presenting disaster and library preservation workshops and has taught the conservation component of the Canberra Institute of Technology's Cultural Preservation course.

Kim Morris can be contacted at:

Preservation Services, National Library of Australia
Canberra ACT 2600
Telephone: (06) 2621597
Facsimile: (06) 2571703
E-mail: kmorris@nla.gov.au


Last updated 9 July 1998

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