Table 2: Storage Life of Microfilms
|
| Anticipated Storage Life |
| |
Film/Type/Parameter |
|
|
| |
Medium Term | Extended Term | Long Term | ||
| ||||
| (Minimum of 10 Years) | (Minimum of 100 Years) | (Indefinitely) | |
|
|
|
| |
|
| Not above 0.030 grams | Not above 0.014 grams | |
Residual Hypo | (1), (2) | per square meter (1) | per square meter (1) | |
|
|
|
| |
Residual Silver Salts | — | No more than perceptible tint by spot stain test. | ||
|
|
|
| |
All Films— |
|
|
| |
Storage Conditions |
| See Table 3 |
| |
Temperature and |
|
| ||
|
|
| ||
Relative Humidity |
|
|
| |
|
|
|
| |
Air Conditioning | Not necessary | |||
| unless film records |
|
| |
| are subjected to |
|
| |
| frequent or sustained |
|
| |
| high humidity (3) |
|
| |
|
|
| ||
Air Purification | Normal | Must be free from airborne gases, dirt particles, | ||
|
| and other contaminants. |
| |
|
|
| ||
Enclosures | Not necessary with | If proper humidity control is provided, plastic or | ||
| moisture control | metal, unsealed, can be used. | ||
| and/or air conditioning | If adequate humidity control is not available, only | ||
|
| metal or glass sealed containers are acceptable. | ||
|
|
|
| |
NOTES:
(1)Expressed as thiosulfate ion.
(2)Specific limits have not been
(3)Dehumidification may be necessary even though automatic air conditioning is not practical.
16 |
