Cellulose Nitrate Still Picture and Motion Picture Film Policy
The storage of all cellulose nitrate still picture and motion picture film is regulated by “National Fire Protection Association (NFPA) 40 — Standard for the Storage and Handling of Cellulose Nitrate Film” Familiarity with this standard is an essential component of collections management of cellulose nitrate film. In addition, transportation of cellulose nitrate film is regulated by the Department of Transportation (DOT Code of Federal Regulations [CFR] 49).
While strong and flexible, nitrate base film has a singular downside: it is highly flammable. Nitrate fires are virtually impossible to extinguish once they start burning. Research has shown that severely decayed nitrate film stored at more than 100° F for more than one week may spontaneously combust (Kodak, Storage and Handling of Processed Nitrate Film); furthermore, in the event of a fire, improperly stored nitrate film could dramatically increase damage to surrounding collections.
There are 5 stages of Cellulose Nitrate Decay:
- Stage 1: Image fading. Brownish discoloration of emulsion. Faint noxious odor;
- Stage 2: Sticky emulsion. Faint noxious odor;
- Stage 3: Emulsion softens and blisters with gas bubbles. More pungent odor;
- Stage 4: Film congeals into a solid mass. Strong noxious odor;
- Stage 5: Film disintegrates into brownish powder.
Generally, once nitrate film reaches Stage 3, it cannot be duplicated. Decay can be slowed by relocating nitrate film to cold storage.
Storage of nitrate film is a problem for all museums, archives, and libraries because new collections are received and new holdings of nitrate film may be found. Therefore, a vigilant Rockefeller Archive Center (RAC) policy for the identification and disposition of nitrate film is necessary.
The RAC continues to identify and segregate cellulose nitrate film. RAC policy requires prompt segregation of all still and motion picture nitrate film from the collections, and removal of the nitrate film to storage that conforms with the provisions of NFPA 40.
The RAC Director of Archives and Assistant Director/Head of Collections Management are responsible for the implementation of this policy. This responsibility includes training staff to identify nitrate film (see: “Nitrate Film Identification and Handling Instructions”) and establishing and implementing procedures for the removal, copying, storage, or possible destruction of nitrate film if physical deterioration dictates such action. All RAC Assistant Directors are responsible for ensuring that their respective teams are familiar with this policy and are diligent in the identification and handling of potential nitrate materials.
As a health and safety matter, all storage of nitrate film is to be reported to the RAC Assistant Director/Head of Collections Management, the Director of Archives and the Operations Manager.
Accepted practice in museums, libraries, and archives is to copy nitrate film onto stable film bases (silver-halide polyester film) or to digitize the images for preservation and accessibility. Proper collections storage space, consisting of cool or cold room environments, is critical for long-term preservation of originals before and after duplication. For unique or highly significant nitrate film, retention of the original after duplication is preferred, even if digital surrogates have been made. Other guidelines are as follows:
Acquisition. Most (though not all) 35mm motion picture film stock manufactured before 1951 is nitrate. It is therefore important to immediately perform a basic visual inspection of the incoming reel(s) to discern whether a film is a pre-1951 nitrate print or a safety copy created after 1951.
A photographic collection that contains any flexible, transparent film negatives from the time period of 1890-1950 is very likely to contain at least some nitrate film. Since these negatives need special attention, they should immediately be separated from other negatives.
Inspection. A RAC Nitrate Evaluation Form must be completed at the accessioning phase. (See: Guide to Collection Management) This form is to be delivered to the Assistant Director/Head of Collections Management and discussed with the Director of Archives where future steps are to be decided.
Rehousing. All nitrate motion picture film is to be re-housed in vented polypropylene film containers during the accessioning phase. Films must be removed from metal reels and stored on 3-inch archival film cores. All film containers that house nitrate material must include a “Nitrate” label that is clearly visible when stacked on a shelf in the film vault, or when placed in cold storage.
Similarly, nitrate photographic material must be segregated from non-nitrate material during the accessioning phase. Select an archival box size for material based upon the dimensions of the majority of those to be contained within an enclosure. Coordinate with Collections Management whenever the project necessitates the use of non-standard containers — including but not limited to: oversized or undersized flat boxes, clamshell boxes, index card boxes, microform boxes, and still image containers. All boxes must include a visible “Nitrate” label. This label must be clearly visible when stacked on a shelf in the film vault, or when placed in cold storage.
Reformatting. For unique or highly significant nitrate film, contracted vendors may provide duplication services.
Transportation within units, to storage, or to reformatting vendors. All transportation of nitrate film is regulated by DOT CFR 49. Nitrate film is considered a class 4.1 flammable solid. When nitrate film is transported using a commercial vendor, packing must comply with DOT Shipping Regulations in 49 CFR 172. In 2012, the US adopted the 16 section Safety Data Sheet to replace Material Safety Data Sheets, formerly used when transporting nitrate. This became effective on December 1, 2013. These new Safety Data Sheets comply with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). By June 1, 2015, employers were required to have their workplace labeling and hazard communication programs updated as necessary – including all MSDSs replaced with SDS-formatted documents. In addition, all container(s) having nitrate material must be labeled to indicate the presence of cellulose nitrate during transport.
Storage. All storage shall comply with NFPA 40.
Disposal. When nitrate material is identified for disposal, the original nitrate film becomes a “hazardous waste,” which is strictly regulated by the Environmental Protection Agency under the Resource Conservation and Recovery Act, and it is managed by federal, state, and local regulations regarding the disposal of hazardous waste.
- Disposal procedure:
Be certain that all parties have signed the Nitrate Evaluation Form approving the disposal of the nitrate material.
Coordinate with the RAC Operations team to make an appointment for the Westchester County Health Facility to pick up nitrate material.
Complete a Household Material Recovery Facility Form (H-MRF).
Pack all nitrate material in a secure, leak-proof container that will not subject H-MRF personnel nor the H-MRF facility itself to any needless exposure of hazardous waste delivered there.
- Disposal procedure:
Author: Andrew Robb; Topics in Photographic Preservation, Volume 10. 2003