R99 en · NOUN
Etymology
From Initialism of Resistant to oil particles with 99% filtration efficiency in NIOSH air filtration ratings.
Meanings
- (uncountable) R99; Ellipsis of NIOSH R99. ▸ R99 standard
- (countable) R99; Ellipsis of NIOSH R99. ▸ R99 filter
Forms
| Spelling | Features | Labels | Source |
|---|---|---|---|
| R99s | Number=Plur | lexicographic |
Coordinates
P100 · N100 (99.97% filtration) · R100