Where service life of apparatus is- | Where percent relative humidity of inspired air is- | Maximum permissible temperature of inspired air shall not exceed- | |
°F. | °C. | ||
1/4 hour or less | 0-100 | 135 | 57 |
1/4 hour to 3/4 hour | 0-50 50-100 | 125 1 110 | 52 1 43 |
1 to 2 hours | 0-50 50-100 | 115 1105 | 46 141 |
3 hours | 0-50 50-100 | 110 1100 | 43 1 38 |
4 hours | 0-50 50-100 | 105 1 95 | 41 1 35 |
1 Where percent relative humidity is 50-100 and apparatus is designed for escape only, these maximum permissible temperatures will be increased by 5 °C (10 °F).
42 C.F.R. §84.103