A dust mask can also be worn in environments with allergens such as tree and grass pollen.
As of 1992, dust masks are not approved by NIOSH, and are not allowed to be used in hazardous environments, where NIOSH-approved respirators are required.
[6] When tested, the dust mask performed worse than a surgical mask in terms filtration efficiency of various-sized particles, but performed the best in terms of airflow.
Filtration efficiency of both surgical and dust masks was considerably worse than the tested NIOSH-approved DM, DFM, and HEPA respirators of the era.
These include: Dust masks[8] have been certified by the United States Bureau of Mines since the 1930s,[9] until being phased out after the passage of 42 CFR 84.