Table K—NIOSH's 1987 Recommended Assigned Protection Factors for Protection Against Gas/Vapor Exposures.
| Assigned Protection Factor[1] |
Type of respirator |
| 10 | Example |
| 25 | Example |
| 50 | Example |
| 1,000 | Example |
| 2,000 | Example |
| 10,000 | Example |
- ↑ The assigned protection factor (APF) for a given class of air-purifying respirators may be further reduced by considering the maximum use concentrations for each type of gas and vapor air-purifying element.
-Any air-purifying half-mask respirator (including disposable) equipped with appropriate gas/vapor cartridges -Any supplied-air respirator equipped with a half-mask and operated in a demand (negative pressure) mode² -Any powered air-purifying respirator with a loose-fitting hood or heimer' -Any supplied-air respirator equipped with a hood or helmet and operated in a continuous flow mode -Any air-purifying full facepiece respirator equipped with appropriate gas/vapor cartridges or gas mask (canister respirator)2 -Any powered air-purifying respirator equipped with a tight-fitting facepiece and appropriate gas/vapor cartridges or canisters³ -Any supplied-air respirator equipped with a full facepiece and operated in a demand (nega- tive pressure) mode² -Any supplied-air respirator equipped with a tight-fitting facepiece and operated in a continu- ous flow mode³ -Any self-contained respirator equipped with a full facepiece and operated in a demand (negative pressure) mode Any supplied-air respirator equipped with a half-mask and operated in a pressure demand or other positive pressure mode² Any supplied-air respirator equipped with a full facepiece and operated in a pressure demand or other positive pressure mode -Any self-contained respirator equipped with a full facepiece and operated in a pressure demand or other positive pressure mode² -Any supplied-air respirator equipped with a full facepiece operated in a pressure demand or other positive pressure mode in combination with an auxiliary self-contained breathing appa- ratus operated in a pressure demand or other positive pressure mode²
- The APF's were determined by Los Alamos National Laboratories (LANL) by conducting quantitative fit testing on a panel
of human volunteers. The APF's were based on workplace protection factor (WPF) data or laboratory data more recently reported than the LANL data.
