Volume 5, Number 1, March 1983, pp.5-6
A symposium on reducing risk to collections of museums, libraries, and galleries was held at the California Academy of Sciences in San Francisco on October 5, 1982. The program was a series of talks divided into 4 sessions ending in a panel discussion.
Details about the probability of earthquake occurrence were discussed by Dr. R. Jahns, citing evidence from various study sites and statistics. He was followed by Dr. Bruce Bolt, who described historic California quakes, their intensities and corresponding degrees of damage. A study site in the San Gabriel Mountains reveals what is thought to be a fifteen century record. Major quakes appear to have occurred at an average interval of 165 years. In the history of the area there have been 10 quakes measuring over 7 on the Richter scale as close together as 34 years (the last quake was in 1952). The San Fernando quake in 1971 was only of moderate intensity. A handout detailing the Modified Mercalli Intensity Scale outlines 12 intensity levels: from an average peak velocity of up to 2 cm per second and average peak acceleration up to 0.02 g (g is gravity=980 cm/sec.2) for levels I through IV to more than 60 cm per second and more than 0.60 g for levels X through XII. A quake at Level I intensity would not be felt. A level VI quake would be felt by all: objects would fall from shelves and pictures from walls; furniture will move, and weak plaster and masonry will crack. Intensity level IX results in heavily damaged masonry, damage to foundations, frame structures not bolted being shifted off foundations, serious damage to reservoirs, underground pipes broken, and conspicuous cracks in the ground. At level XII damage is nearly total: large rock masses are displaced, lines of sight and level distorted, objects thrown into the air.
The next topic in this session dealt with the risk of fire and water damage to collections after a quake. San Francisco Fire Department Chief, Emmet Condon, spoke about what kind of help is or will be available. He mentioned that utility companies have maps of flood plains, high pressure mains, etc., helpful in discerning risks to particular locations. He discussed types of alarms and automatic fire extinguishing systems and problems caused by air handling systems and materials used in furnishings. The S.F. Fire Department carries large fans and vacuums as well as portable heating units for drying wet areas. He stresses, however, that after a major earthquake, response time to a call from a museum would be, at best, 18 to 24 hours. (Remember that the bridges may close, and many firemen live outside the city.) The emphasis falls on preparedness. Fire safety training courses are available through the Community Colleges.
Dr. John A. Blume talked about the dynamic and harmonic vibrations or frequency range that all objects have as well as ductile versus brittle properties. He discussed methods of reinforcing or anchoring objects and displays bearing in mind what type of vibration the work of art and its display area are vulnerable to, including objects on display outdoors, where one must consider the soil structure and how it would react in an earthquake. He described what a structural engineer can provide to help in planning. Dr. Henry J. Lagorio gave more specifics on how to stabilize storage and display areas. For example, displayed objects could be secured with barely visible guide wires; glass cases could be lashed or bolted together to prevent them from colliding; cases and shelves can be bolted to the wall, floor, or ceiling, although some heavier cases may be safer if allowed to "walk" with the motion of the earth. Other practical considerations to minimize damage to falling objects include restraints for shelving (cords or a lip along the edge), padding of shelves, drawers, or even the floor. Also, it is important to consider what parts of a structure might fall: lighting fixtures, air ducts, etc.
This session's speakers had pointers for specific types of collections. Katherine Holland of S.F.M.O.M.A. described what can be done in art museums and galleries. Among the ideas implemented for the collection she works with are storing duplicate records and photographs and information on the collections at a different location and using heavy bottomed packing boxes well padded against shock, with a photograph of the object adhered to the box.
John Verity, Manager of Library Division, Lawrence Livermore Laboratory had slides of a library in his charge after the recent earthquake near Livermore which were frighteningly enlightening about shelving that has not been securely anchored.
Geoffrey Brown of the Lowie Museum of Anthropology gave more information on storage areas, including possible use of fishnet restraints for shelving and discussion of problems with padding that could produce a "trampoline" effect.
Concerns specific to natural history collections were addressed by Jean DeMouth Smith of the California Academy of Sciences. These include wet specimens in formalin or alcohol, pressed botanicals, insects, minerals, and rocks.
Gary Matteson, College of Chemistry, U.C. Berkeley had many ideas including the designation of "safe areas", runner systems for communication, training and assigning of duties reinforced by drills, photo displays and survey sheets to be filled out on a scheduled basis.
Rigo D. Cabezas, Vice President of Johnson and Higgins Insurance Brokers of San Francisco, stressed the importance of detailed records with duplicates stored at a geographic locale well away from the state, if possible. Ideally, records should include replacement values for the articles. He recognized that earthquake insurance is quite expensive to obtain, although it does vary considerably on the nature of the building's construction. Many companies have inspectors who can evaluate a facility and may come up with important information about the structure.
Dr. Herbert Thier gave encouraging guidelines on developing public awareness as a key to protection of public, collections, and staff. He discussed the California Earthquake Education Project, funded by the State, that he is currently working on.
Perhaps the most useful product of the symposium was the summary, prepared by Joan Bacharach, of a paper presented by John E. Hunter at the Seminar on the Protection of Historic Architecture and Museum Collections from Earthquakes and other Natural Disasters, given in March, 1982 at the National Academy of Science in Washington D.C. Her outline, in brief, is as follows:
A. Development of Disaster Plan
1. Designation of an organizing committee given authority in writing
2. Location of sources of assistance
3. Assessment of vulnerabilities and priorities
4. Survey of collections, data, facilities, equipment, and people, evaluated according to safety/value
5. Methods of protection
6. Recovery plan
7. Writing and circulation of plan
B. Written Disaster Preparedness Plan
1. Statement of purpose
3. Scope of events, structures affected, degree of risk
4. Disaster avoidance
5. Unavoidable but expected disasters - emphasis on preparing collections
6. Unexpected disasters - emphasis on recovery. Plan must be constantly updated by appendices: staffing charts, facilities control, and communication. volunteers. equipment, source lists
C. Training & Evaluation of Plan
1. Training of the staff
3. Evaluation of plan
Multihazard Assessment of Locale & Site
1. Damaging forces
2. Agents- chemical, biotic
3. Evaluation of structure
4. Assessing seismic vulnerability
5. Reducing of vulnerability
6. Protection of collections and exhibitions.
The symposium was concluded with a brief panel discussion allowing members of the audience to ask the speakers any specific questions they had about the topics discussed.Reported by Anita Noennig, Oakland, CA