Records Managers

Managing X-ray Films as Federal Records

2000 Web Edition

Note: This is a Web version of Managing X-ray Films as Federal Records, National Archives and Records Administration, Office of Records Services, College Park, MD (2000), 10 pp. Historical photographs that were used for illustration purposes only in the paper publication are not currently incorporated into this version.

Table of Contents


X-ray films pose a challenge in the field of records management for two principal reasons. First, though rarely appraised as permanent records, they are frequently scheduled for very long retention periods, often as long as 75 years and, in some cases, even longer. Second, as film-based materials are vulnerable to damage from inappropriate storage environments, special precautions are needed to keep them in good condition until authorized for disposal. This guidance is primarily directed at the management of X-ray films maintained as separate series. Segregation of X-ray films from case files also containing paper records makes storage of the film under proper conditions more cost-effective. The National Archives and Records Administration (NARA) recommends that agencies avoid interfiling X-ray films within paper files because off-gassing from paper can cause chemical changes in the film base or emulsion. However, interfiling of X rays within case files remains a common practice in the Federal Government.

X-ray Files are Important Records

X-ray files are retained for long periods to ensure the protection of individual rights, as evidence in potential claims against the Government, and for other reasons. They are often used to
  • Monitor the health of Federal employees exposed to radiation or other problems related to industrial hygiene

  • Diagnose the health of persons entering or separating from military service

  • Treat enlisted personnel and qualified dependents

  • Monitor the health of Native Americans receiving treatment at Government-administered medical clinics

  • Serve as baseline data in long-term epidemiological studies

  • Document the management of nuclear reactors, construction of buildings, and the analysis of equipment or products

  • Provide evidence in a court proceeding

Records Managers Should

  • Become familiar with the storage requirements for basic types of X-ray films

  • Ensure that separate series of X-ray films are placed in storage conditions appropriate for the number of years films are to be retained

  • Ensure that steps are taken to replace harmful filing enclosures or envelopes

  • Ensure that conditions of storage and use protect individuals' medical privacy

X-ray Film Types

The first X rays were recorded on glass plates coated with a photographic emulsion. In 1918 Eastman Kodak introduced X-ray sheet film coated on both sides. Over the years there have been three basic film types: nitrocellulose or nitrate, safety cellulose acetate, and polyester. Currently some X rays (and other medical imaging scans) are made and stored as digital files or scanned from film originals; either source can be printed out to hard copies on film or paper. NARA plans to include a section on digital X-ray files in its guidance on the management of electronic records.

Nitrate based - 1910s to 1930s

  • Highly flammable and akin to gun cotton, nitrate film deteriorates as it ages, emits an obnoxious odor, discolors to amber, and becomes sticky and brittle. The word "nitrate" is imprinted on the film. Nitrate film may be combustible under extreme storage conditions, especially where temperatures exceed 100 degrees Fahrenheit and the humidity is in the upper ranges.

Acetate based - 1920s to mid-1960s

  • Manufactured as a "safety film" (the words are imprinted on the film’s edge), acetate film is flame resistant. However, it deteriorates as it ages, emitting a vinegary odor derived from vapors of acetic acid, a phenomenon preservationists call the "vinegar syndrome." Once deterioration begins, the chemical process becomes autocatalytic, perpetuating at a faster and faster rate. As the base shrinks, the emulsion starts to separate from the base in the form of cracks and channels, and the film becomes brittle and eventually shrivels or buckles beyond use.

Polyester based - mid-1950s to the present

  • The most stable base, polyester film tends to resist chemical and physical changes as it ages under varied storage conditions. The word "safety" is imprinted on the film’s edge. Some Kodak films are labeled "Estar," a proprietary polyester film.

Other formats

  • Other X-ray formats include micrographic images like microfilm and aperture cards, which must also be stored under conditions that will ensure availability for their full retention period. For additional information, see 36 CFR Part 1230, Micrographic Records Management.

Storing X-ray Films

Since storage conditions significantly influence rates of deterioration, good conditions can extend film’s useful life. The film base, to be sure, plays an important role. But regardless of base, the black-and-white silver image is vulnerable to excessive heat and moisture and to harmful gases such as sulfur dioxide and nitrogen oxides often found in urban and suburban environments. Organic compounds such as gelatin containing the photographic emulsion become susceptible to fungal growth in storage areas where the Relative Humidity (RH) exceeds 60 percent.

Nitrate-based film


  • Safety concerns are paramount. Remove from records storage areas and place in conditions that do not exceed 70 oF and 50% RH. Storage in a freezer or cold storage is highly recommended.
  • Likely to be in the poorest condition.
  • Copy to polyester film and, after verification of the copy, destroy in accordance with applicable regulations governing the disposal of hazardous waste. (EPA Hazardous Waste Code, D001, D003, and D0011)
  Extended Storage
  • For long-term storage, store the film at 35 of and 20-30% RH, as recommended by Eastman Kodak.
  • Store in accordance with the requirements of the National Fire Protection Association Code NFPA-40, Standard for the Storage and Handling of Cellulose Nitrate Motion Picture Film, which describes building and fire safety specifications for the storage of nitrate film.
  • Ventilation may be needed depending upon the quantity of stored film. Store separately from other types of photographic records as off-gassing can accelerate deterioration of nearby film in good condition.
  • The packing and shipping of nitrate film are governed by the following Department of Transportation regulations: 49 CFR 172.101; 172.504; 173.24; and 173.177.
Acetate-based film
  • Likely to be in degraded condition, having been stored for at least 20 years under office storage conditions or worse.
  • Place in cool and dry storage conditions to slow down deterioration.

  • Research shows that storage temperatures from 35 to 55 of, at 50% RH, can extend degraded film’s life from 15 to 75 years longer, depending on the state of deterioration of the film.
  • Only American National Standards Institute (ANSI) cold storage recommendations for acetate film will ensure preservation for 100 years or more (ANSI/PIMA IT9.11).

Acetate Storage

Medium Term
(1 to 10 Years)
77o 20%-50%
Long Term
(11 to 50 Years)
70o 20%-50%
(51 to 100 Years)
35-45o 20%-50%

Polyester-based film

  • Virtually all X-ray film used in the last 30 years is polyester based.
  • Highly resistant to chemical changes, polyester film has excellent long-term storage characteristics that normally extend its longevity beyond records retention requirements.

Polyester Storage

Medium Term
(1 to 10 Years)
77o 20%-50%
Long Term
(11 to 50 Years)
70o 20%-50%
(51 to 100 Years)
70o 20%-50%

Other Storage and Use Considerations


  • Like any Federal records, X-ray files must be scheduled in accordance with NARA regulations (36 CFR Part 1228).
  • Unidentified X-ray films and those in advanced stages of decomposition that can neither be interpreted nor copied should be destroyed. Since acetate and nitrate in advanced stages of decomposition can damage nearby records in good condition, and since decomposing nitrate poses a fire hazard, these records may be destroyed and subsequently reported to the Archivist of the United States. (36 CFR 1228.92(b))
  • Where it is economically feasible, agencies should endeavor to recover the silver content from disposable film (41 CFR 101-45.10).

Enclosures for X-ray films

  • For medium-term retention (up to 10 years) store each sheet in a high-quality X-ray envelope.
  • For long-term retention (over 10 years):
    • Nitrate-based:
      Store in individual lignin-free, buffered paper envelopes. However, copying and disposal of nitrate are advisable.
    • Acetate-based:
      Store in individual lignin-free, buffered paper envelopes.
    • Polyester-based:
      Store in individual lignin-free, buffered paper envelopes or plastic sleeves made from polyester, polyethylene, or polypropylene.
    • For very long retention, use enclosures specified in ANSI standards IT9.2 and IT9.16.
  • For offsite storage, use heavy-duty cartons marked "X-ray Files - Store Vertically."


  • Older X-ray films become embrittled and break easily.
  • Physical handling is extremely detrimental.
  • Use white cotton lint-free gloves when handling X-ray films.
  • Avoid placing nitrate film in contact with heat sources such as a light bulb or electrical equipment since nitrate’s flashpoint or ignition occurs at relatively low temperatures.

Health and Safety

Large stores of acetate film in poor condition emit obnoxious gases (primarily vapors of acetic acid) that are harmful to persons when ingested or inhaled or when the gas buildup exceeds 10 parts per million (29 CFR 1910.1000)

  • Ventilation or air exchange is needed for acetate and nitrate films unless the films are stored below freezing where chemical activity and aging is slowed.
  • When working with degraded or deteriorating acetate or nitrate film, use gloves made of impermeable plastic, goggles, and respirators with organic and acid vapor filtration.


  • Several copying methods are available:
    • Film to film
    • Camera copies
    • Microfilm
    • Slides
    • Film to glossy paper
    • Digital processes which can yield hard-copy printouts
  • Film copies should be made in accordance with ANSI specifications (ANSI/PIMA IT9.1).
  • For record or documentation purposes, reducing images to less than half their original size is not recommended.


  • Since files of X-ray films are relatively heavy, especially chest X rays, they require heavy-duty shelving.
  • Safe storage of a large series may also require special floor support depending upon the weight load.
  • Store X-ray films vertically; stacking puts pressure on the lower ones, causing damage.

References and Further Reading

American National Standards Institute, 11 W. 42nd St., New York, NY 10036:

   ANSI/PIMA IT9.1-1996: Imaging Media (Film) - Silver-Gelatin Type - Specifications for Stability.

   ANSI/PIMA IT9.2-1991: Imaging Media - Photographic Processed Films, Plates, and Papers - Filing   Enclosures and Storage Containers.

   ANSI/PIMA IT9.11-1993: Imaging Media - Processed Safety Photographic Films - Storage.

   ANSI/PIMA IT9.16-1993: Imaging Media - Photographic Activity Test.

Eastman Kodak. Safe Handling, Storage, and Destruction of Nitrate-Based Motion Picture Films, Kodak Environmental Services (H-182), 1995.

Image Permanence Institute. IPI Storage Guide for Acetate Film. IPI/Rochester Institute of Technology, 1993. Image Permanence Institute, Gannett Memorial Bldg., P.O. Box 9887, Rochester, NY 14623.

National Archives and Records Administration. Managing Audiovisual Records, 2nd ed., NARA: College Park, MD, 1996.

_____. Cold Storage Handling Guidelines (available on the NARA web site,

National Fire Protection Association. Standard for the Storage and Handling of Cellulose Nitrate Motion Picture Film, 1994 ed. (NFPA-40). NFPA: Batterymarch Park, MA, 1988.

Records Managers >

The U.S. National Archives and Records Administration
1-86-NARA-NARA or 1-866-272-6272