Section 1237.18 - What are the environmental standards for audiovisual records storage?(a)Photographic film and prints. The requirements in this paragraph apply to permanent, long-term temporary, and unscheduled audiovisual records.(1)General guidance. Keep all film in cold storage following guidance by the International Organization for Standardization in ISO 18911 (incorporated by reference, see § 1237.3 ). See also ISO 18920 (incorporated by reference, see § 1237.3 ).(2)Color images and acetate-based media. Keep in an area maintained below 40 degrees Fahrenheit with 20-40% relative humidity to retard the fading of color images and the deterioration of acetate-based media.(b)Digital images on magnetic tape. For digital images stored on magnetic tape, keep in an area maintained at a constant temperature range of 62 degrees Fahrenheit to 68 degrees Fahrenheit, with constant relative humidity from 35% to 45%. See also the recommendations in ISO 18923 (incorporated by reference, see § 1237.3 ); and the requirements for electronic records storage in 36 CFR 1236.28 .(c)Digital images on optical media. For permanent, long-term temporary, or unscheduled digital images maintained on optical media (e.g., CDs, DVDs), use the recommended storage temperature and humidity levels stated in ISO 18925 (incorporated by reference, see § 1237.3 ).