84.1149—Airflow resistance tests; all dust, fume, and mist respirators; minimum requirements.
(a)
Resistance to airflow will be measured in the facepiece, mouthpiece, hood, or helmet of a dust, fume, or mist respirator mounted on a test fixture with air flowing at a continuous rate of 85 liters per minute, both before and after each test conducted in accordance with §§ 84.1144 through 84.1147.
(b)
The maximum allowable resistance requirements for dust, fume, and mist respirators are as follows:
| [mm. water-column height] | |||
| Type of respirator | Initial inhalation | Final inhalation | Exhalation |
|---|---|---|---|
| Pneumoconiosis- and fibrosis-producing dusts, or dusts and mists | 12 | 15 | 15 |
| Dust, fume, and mist, with single-use filter | 30 | 50 | 20 |
| Dust, fume, and mist, with reusable filter | 20 | 40 | 20 |
| Radon daughter | 18 | 1 25 | 15 |
| Asbestos dust and mist | 18 | 25 | 15 |
| 1 Measured after silica dust test described in § 84.1144 . | |||