burn experiment

Exploration of Salvage Techniques: Fire-Damaged Materials

Preliminary Process:
As was the case with our experiment salvaging flooded materials, we chose items we believed would best represent collections within libraries, archives, and museums. The materials were arranged on a bookshelf and desk to resemble an office environment. The following is a partial list of the materials included.

Paper Materials:

Book inside an archival tuxedo box
Hardback books (dictionaries, technical studies volumes, etc...)
Paperback books
Journals
Plastic file folder with two newspapers and one magazine
Manuscript box filled with documents in folders
Documents in manila folders
Folded road maps
Architectural drawings
Newspapers

Audio-Visual Materials:

Binder with slides and photos in plastic, non-archival sleeves
Bindered photo album with plastic sleeves
Plastic sheet with slides
Roll of 16mm film

VHS tapes
DVD
Plastic box holding floppy disks
Reel to reel audio tape
Two polypropylene canisters with audio reel inside (one was fire resistant)
Cassette tapes in plastic cases
Vinyl record album in a cardboard sleeve

Objects:

Laptop
Computer system unit
30” x 36” acrylic painting on strainer
Small ceramic tea pot
Cardboard manuscript box full of fabrics
Three wicker fans

In the lab, we arranged these items on the bookshelf and on the desk before going to the Austin Fire Department Training Center. The objects were numbered in order to keep track of which materials sustained the most damage. We also took pictures of how the items were organized to provide visual documentation. The objects were then packed in crates and boxes. We kept careful track of where we had placed the items in order to recreate the office environment once we arrived at the training center.

The Experiment:
We collaborated with the Austin Fire Department to simulate an arson fire. The Austin Department provided space, a small room constructed within a metal shipping container with painted walls, carpet, and a window. We arranged the bookshelf against one wall and the desk along an adjacent wall, positioned underneath a slightly opened window. Once the items were arranged, the firefighters used an accelerant to ignite a strip of cloth that had been positioned to extend from the bookshelf to the desk. The door of the room was closed and the fire was left to burn for approximately twenty minutes. When it seemed the materials had burned sufficiently for our experiment, the fire was extinguished using a hose. Upon examination we found the fire had not touched the computer or the materials on the desk. We asked that another be set, and the second fire was allowed to burn until we were satisfied with the level of damage caused. It was, again, extinguished using water. The items were left to sit for two days before we retrieved them and transported them back to the lab for salvage procedures. That two day delay allowed sufficient time for water damage but minimized the risk of mold growth.

Aftermath:
When we returned to the site, our first task was to assess the damage. The bookshelf, and especially the lower three shelves, was heavily damaged by fire and damaged to a lesser extent by the water used to extinguish it. Much of the paper was singed and some was damp. Several of the plastic cases had melted. Generally, housings such as cases, boxes, and sleeves were effective at reducing damage. The metal film cans protected the film inside more effectively than the plastic cans. Melting and distortion, especially of the reels, occurred on the plastic cases. In both cases the film appears to be playable, although we have not run it through a projector. Interestingly, there was no discernible difference between the regular plastic film can and the one labeled fire resistant. The vinyl record was warped. The audio cassette cases melted, but when we put them in a cassette player the sound was clear and seemed unchanged. The plastic box containing the floppy disks melted but the disks inside appeared to be unharmed. Plastic items above the second shelf, such as the VHS tapes, were mostly unharmed. Some of the hardback books and newspapers were charred, and most paper items were slightly wet from extinguishing the fire. In general, we found that items on higher shelves incurred less direct damage from fire and water, however, soot was found on items from all shelf levels.

Salvage Procedures:
Informed by our previous experience salvaging materials from a flood, we began triage. Since this was not actual collection material, but materials with little or no value that had been assembled for our educational experience, we kept examples of diverse materials and types of damage, but discarded duplicates. For instance, we considered five charred and damp paperbacks to be representative of the other twenty or so that we discarded.

Soot Removal: By gently wiping objects with soot sponges, we were able to remove most of the soot from selected items. We also found this technique to be effective on architectural drawings, the maps, and the tea pot. For other objects, we used hake brushes (a wide-handled brush with long, soft goat hair bristles) to gently remove soot and small debris.
Air Drying and Interleaving: We covered a table with blotter paper and placed objects there to dry. Books that were damp were interleaved with blotter paper or paper towels. The absorbent paper was changed as often as our chaotic student schedules would allow to prevent mold growth. Some of the paperback books were placed upright and opened to a 45 degree angle. We interleaved one of the paperback books with Zorbix paper, a super absorbent material used to speed air-drying. Photographs and slides were gently washed in clean water before being laid flat on blotter paper to dry.
Removal of Melted Containers: The heat from the fire caused the plastic archival canisters housing film to fuse shut. We tried to open them first by gently prying the lid from the base, then we tried cutting the canisters open with a knife. After our attempts to extract them more delicately failed, we broke them open with a hammer. This would be an unsatisfying approach for collection material, but proved effective for our purposes.

End Results:
During our next class, after waiting a period of one week, we assessed the effectiveness of our salvage attempts.

Most objects dried: Most of the bound and paper materials we interleaved and placed on blotter paper managed to dry with some warping but no mold growth.

Some of the objects contorted: Rinsing the photographs effectively separated them from one another, preventing the emulsion from becoming permanently stuck. After air drying they were slightly cockeled, but could easily be flattened. Although the cases of some cassettes were melted, the tapes were still playable.

Some of the objects were stained: Soot sponges were used to clean the surface damage of some objects, but permanent staining did occur. One newspaper was charred around the edges. Although this was an unavoidable consequence of the fire rather than a reflection of our salvage techniques, one page was placed between Mylar to keep the brittle edges from easily breaking off. This was to illustrate how to protect it from further damage.

Melted plastic: After gaining access to the tapes housed in the fire retardant cases, we found that the edges of the tapes had melted slightly. Unfortunately this damage could not be reversed.