Respiratory Protection: Selection, Fit Testing, and Program Basics

29 CFR 1910.134 · Respiratory Protection

Keywords: respiratory protection program, fit testing OSHA, NIOSH approved respirator, air-purifying vs supplied-air, PAPR half-face respirator, assigned protection factor, IDLH atmosphere

Respirator Selection Logic

Assigned Protection Factors (APF)

• Half-face APR: APF = 10 (max use concentration = 10x OEL)
• Full-face APR: APF = 50
• Powered air-purifying (PAPR): APF = 25 (half-face) or 1,000 (full-face/hood)
• SCBA pressure-demand: APF = 10,000
• Never use an APR in IDLH conditions regardless of cartridge type.

Written Program Requirements

• Every employer requiring respirators must have a written program administered by a designated program administrator.
• Medical evaluation must be done before fit testing and before any respirator use.
• Fit testing: quantitative or qualitative — must be done annually and when physical changes occur (significant weight change, facial surgery, new dentures).
• User seal checks required every time the respirator is donned.
• Voluntary use of filtering facepieces (dust masks) requires at minimum the appendix D information sheet.

Common Respiratory Exam Traps

• Fit testing is not the same as a medical evaluation — both are required and neither substitutes for the other.
• Cartridge change-out schedules must be based on an objective schedule (e.g., calculations, manufacturer data) — "change when you smell it" is not acceptable for most contaminants.
• Beards and stubble that cross the sealing surface make fit testing invalid and the respirator non-protective.
• Air-purifying respirators do NOT provide protection against oxygen deficiency — a gas mask in an O₂-deficient space will not help.
• SCBA cylinders must be ≥90% full before entry — not just "not empty."