A “Dangerous” Film, or the Case of the Misbegotten Label

8, January 2013
Film can and protective gear on a cartA film can and protective gear are loaded onto a fireproof cart and taken outside as a precaution before the film canister can be opened and examined.

Film cans often sit for years on shelves, awaiting the care of a professional film archivist, curator, or qualified preservationist to identify, document, repair, and conserve their contents. One of the more problematic kinds of film that we occasionally encounter in our work is nitrate film. The earliest film base (the material to which the film emulsion adheres) was made of nitrate cellulose. Using camphor to plasticize “nitrocellulose,” Kodak and other film suppliers began making nitrate film as early as the late 1880s, originally for still photography, then later for motion picture film.

Nitrate is a highly flammable compound, which can be used as a combustible propellant or explosive. Over the last century, nitrate-based film developed a reputation for causing fires in both theatres and storage vaults, but much of this reputation is exaggerated. Although projection booth fires were more common and occasionally included loss of life, there have been only 15 documented cases of vault fires, worldwide, in the last 100 years. In all of those cases, the film had been neglected and exposed to extremely high temperatures, which caused it to auto-ignite. Because cellulose nitrate contains its own oxygen, these fires are almost impossible to extinguish and will even continue to burn underwater. Generally, the fires must be allowed to burn until the film has turned to ash.

Film preservationist in gearFilm preservationist Kelly Kreft dons protective gear before opening a canister suspected of containing nitrate film.

Here at the Museum, one film can has been patiently waiting in a stable, climate-controlled environment to be evaluated. This can was sealed with black tape and labeled “1931 Veiled Prophet.” It was marked as unusable nitrate film in stage two of deterioration. Film preservationist Kelly Kreft and I gathered a few potentially necessary tools and personal protective gear—gloves, respirators (nitrate film that has gone bad can also off-gas dangerous nitric acid fumes), and goggles—to open this “dangerous” can of film. We placed the film can onto an aluminum, fireproof cart and took it outdoors, a safe distance from any building (just in case of fire) and prepared to open the can. After we “suited up,” we opened the can.

Immediately, I began to laugh and Kelly moaned in disappointment. The film was 16mm. Nitrate was never used as a film base for 16mm film. The two reels of film within the can were decomposing acetate film—meaning not nitrate and not dangerous. We were hoping to find deteriorating nitrate film, something that is no longer commonly seen. However, because of the outcome, it is possible to some day restore the film.

After our discovery, we returned inside and prepared the “1931 Veiled Prophet” film for freezer storage. This is just one of the many adventures our curatorial staff experiences when we encounter artifact containers with misidentified labels. 

—Klara Foeller, Curator of Moving Image and Sound Collections