Ensure that no employee is exposed to an airborne concentration of respirable crystalline silica in excess of 50 ?g/m3, calculated as an 8-hour time-weighted average (TWA).
Or. Admin. Code § 437-002-1055
Stat. Auth.: ORS 654.025(2), 656.726(4).
Stats. Implemented: ORS 654.001- 654.295