Effects of Water Vapour on the Performance of Respirator Gas and Vapour.
NIOSH 1980 Sep:163-179
The effects of moisture on the performance of gas and vapor filters used in respirators were investigated. The rates of water uptake by six different filter types were investigated using a two step procedure involving humidification under dynamic conditions and under static conditions. The effects of equilibrating filters with water vapor before testing were investigated in a comparative study using a number of filters. The author concludes that a dangerously low level of protection occurs in many cases as a result of the lowering of the breakthrough time due to the substantial amount of water vapor sorbed from the air and recommends that a new draft for a European standard specify that breakthrough tests on respirator filters be performed only after the filters have been equilibrated with water vapor at about 30 liters per minute, about 70 percent relative humidity, and about 20 degrees centigrade.
Materials-testing; Safety-equipment; Filter-materials; Respiratory-protective-equipment; Personal-protective-equipment;
Control Technology and Personal Protective Equipment; Research Tools and Approaches;
Papers from the NIOSH International Respirator Research Workshop, September 9-11, 1980, Division of Safety Research, NIOSH, Morgantown, WV