N99 (English, noun)
expansion: N99 (countable and uncountable, plural N99s)
Senses:
glosses: N99; Ellipsis of NIOSH N99.
N99 standard
tags: uncountable
glosses: N99; Ellipsis of NIOSH N99.
N99 filter
tags: countable
Forms:
form: N99s
tags: plural