NARA Bulletin 2023-01
December 20, 2022
TO: Heads of Federal agencies
SUBJECT: Guidance on Storing Radiographic Film Records
EXPIRATION DATE: Expires when revoked or superseded
1. What is the purpose of this bulletin?
This bulletin provides agencies with general storage guidance for radiographic film as federal records, in accordance with 36 CFR Chapter XII Subchapter B, parts 1234 and 1237. Radiographic film consists of a clear plastic base with an electromagnetic radiation-sensitive silver gelatin emulsion. X-rays are the most common type of radiographic record.
Because radiographic film records are often scheduled for long retention periods, up to 75 years or more, they are distinguished from similar media such as film-based moving images, still transparencies, and negatives with typically shorter retention times. All film-based materials are vulnerable to damage from inappropriate storage environments, and special precautions are needed to keep them in good condition until authorized for disposal or transferred to NARA.
2. What are the types of radiographic film?
There are three types of radiographic film material -- cellulose acetate, polyester, and cellulose nitrate (or nitrate). Each has specific health, safety, and storage conditions to consider.
- Cellulose acetate film was used from the 1930s to 1960s and is flame resistant and often marked as "safety film". Under poor storage conditions it will deteriorate and emit a vinegar odor (often referred to as "vinegar syndrome"). Cool and dry environmental conditions are essential to long term storage.
- Polyester film, used from the early 1960s to the present day, is chemically and physically stable if stored at proper environmental conditions.
- Cellulose nitrate film was used for X-rays until the early 1930s and for sheet film, 35 mm motion pictures, aerial and still photography into the 1950s. Nitrate film is rarely found in agency records. It will deteriorate and emit an odor under poor storage conditions.
Records managers must identify the types of film maintained by their agency and ensure the proper storage requirements are used for each type of film.
3. What are the required storage conditions for radiographic film?
Agencies must follow the storage requirements 36 CFR Chapter XII Subchapter B, parts 1234 and 1237 for records on film. Agencies must ensure that radiographic film records are placed in storage conditions appropriate for the type of film. Cellulose acetate and polyester film must be stored according to ISO 18911 Imaging materials -- Processed safety photographic films -- Storage practices. Due to its flammability, cellulose nitrate film must be stored according to the National Fire Protection Association NFPA 40 standard.
4. What are additional considerations for storing radiographic film?
Agencies should refer to 36 CFR Chapter XII Subchapter B, part 1237.30 for additional guidance for managing cellulose nitrate and acetate film. NARA recommends that agencies avoid interfiling paper and X-ray records. Film may off-gas (a chemical deterioration by-product) and contaminate adjacent paper. Also agencies should take steps to remove or replace harmful storage enclosures or envelopes.
5. What additional requirements apply to managing radiographic film?
This bulletin describes the physical storage of radiographic records. Agencies should refer to 36 CFR Chapter XII Subchapter B, part 1237.30(b) for the periodic inspection requirements for cellulose acetate film. This bulletin does not address other records management requirements in NARA guidance, such as creating records schedules for radiographic records. Agencies should refer to appropriate information governance statutes and regulations, such as the Privacy Act and Freedom of Information Act (FOIA), especially as radiographic film can often contain personal sensitive information.
6. Whom do I contact for more information?
If you have questions about radiographic records in your agency, please contact your agency’s Records Officer. A list of agency Records Officers can be found on the NARA website at https://www.archives.gov/records-mgmt/agency. If you have questions about any part of this bulletin, please contact NARA at: rmstandards@nara.gov.