(a) Three non-powered respirators will be tested in accordance with the provisions of Sec. 84.1144, or equivalent, and shall meet the minimum requirements of Sec. Sec. 84.1144 and 84.1149.
(b) Three powered air-purifying respirators will be tested in accordance with the provisions of Sec. 84.1144 except they will be tested for a period of 4 hours each at a flowrate not less than 115 liters per minute to tight-fitting facepieces, and not less than 170 liters per minute to loose-fitting hoods and helmets. The total amount of unretained test suspension in samples taken during testing shall not exceed 14.4 milligrams for a powered air-purifying respirator with tight-fitting facepiece, and 21.3 milligrams for a powered air-purifying respirator with loose-fitting hood or helmet. They shall meet the minimum requirements of Sec. 84.1149.