Storage of magnetic materials

Recommended storage conditions for magnetic tape, both audio and video:

Agency	Year	Temperature	Relative Humidity
SMPTE (RP-103)
Operating ¹	1995	17°C to 25°C	30% to 70% +/- 5%
Storage <10 years ¹ (short term)		15°C to 23°C +/- 2°C	40% to 55% +/- 5%
Storage > 10 years (long term)		17°C +/- 2°C	30% +/- 5%
ANSI/AES
Medium Term	1996	23°C (max) +/- 2°C	20% to 50% +/- 10% ⁴
Extended Term ²		20°C (max) +/- 2°C ³	20% to 30% +/- 5% ⁴
		or 15°C +/- 2°C ³	20% to 40% +/-5% ⁴
		or 10°C +/-2°C	20% to 50% +/- 5% ⁴

1. For operating or storage less than 10 years, the centre point for temperature and humidity can be selected anywhere within the allowable range, but the variation cannot exceed the allowable range.

2. For / Extended-Term Storage, a lower storage temperature can compensate for a higher humidity to provide the same life expectancy and a wider relative humidity range can be tolerated. For this reason, several relative humidity-temperature combinations can be used for an extended term storage environment as specified above.

3. Storage of tape below 8°C (46°F) may cause lubricant separation from the tape binder. The manufacturer should be consulted to determine if this is a potential problem.

4. The moisture content of the tape to be stored shall not be greater than the tape in moisture equilibrium with this relative humidity.

Note: concerning storage of video tape, the Ampex Corporation recommends temperatures between 18 and 21°C (65-70°F). and 35 to 45 per cent relative humidity. The environment should be kept as constant as possible, because fluctuations can cause damage through expansion and contraction of wound tape. Dust must be kept to an absolute minimum.