OEMS Occupational Exposure Management Systems LLC
OEMS Occupational Exposure Management Systems LLC
Exposure assessment tools for Health & Safety Professionals

Maximum Use Concentration (MUC) Calculator

Calculates the maximum use concentration as APF × OEL, using the OSHA 1910.134 Table 1 APF for the selected respirator, and caps it at the IDLH when one is entered.

Name of the chemical or agent.

OSHA PEL, ACGIH TLV or other limit the program uses.

Units for the OEL, IDLH and results.

NIOSH IDLH in the same units. Leave blank if none.

Class and facepiece from the APF table below.

Maximum use concentration

Lower of APF × OEL and the IDLH

Assigned protection factor (APF)
Calculated MUC (APF × OEL)
IDLH

OSHA Assigned Protection Factors

Respirator TypeAPF

Source: OSHA 29 CFR 1910.134(d)(3)(i)(A), Table 1, Assigned Protection Factors; 1910.134(d)(3)(i)(B), Maximum Use Concentration; 1910.134(d)(2), respirators for IDLH atmospheres. APR = air-purifying respirator; PAPR = powered air-purifying respirator; SAR = supplied-air (airline) respirator; SCBA = self-contained breathing apparatus. Filtering facepieces take the half mask APF of 10 (Table 1, note 2). Helmet/hood APF of 1,000 requires manufacturer WPF or SWPF test evidence at 1,000 or more; otherwise 25 (Table 1, note 4).