Respirator selection
Styrene respirator selectionC8H8
Monomer for polystyrene, ABS, SBR rubber, and unsaturated polyester/fiberglass-reinforced plastics. Plastics, composites, boat/tub fabrication.
These are federal OSHA limits. The PEL shown is the federal OSHA value. About two dozen states run their own OSHA-approved plans, and some — notably California (Cal/OSHA) — enforce lower or additional exposure limits. If you work under a state plan, check your state's PEL and enter it as a custom limit in the calculator.
Recommended cartridge: Organic Vapor (OV) — Black band
An APR fitted with the correct cartridge is only adequate up to its MUC (below) — the cartridge must be able to capture styrene. VERIFIED against NIOSH npgd0571: OV chemical-cartridge respirators are recommended up to 500 ppm (APF 10) and full-facepiece OV to 700 ppm (APF 50). Strong odor gives good warning. IDLH 700 ppm. Not flagged Ca in the current NIOSH Pocket Guide, though styrene is now classified a probable/anticipated carcinogen (IARC 2A / NTP) — consider supplied air for prolonged high exposure. You must establish a change-out schedule; never rely on taste or smell. See the cartridge & filter guide.
The OSHA limit for styrene is a ceiling value, not an 8-hour average. The MUC method below is defined for time-weighted limits, so apply professional judgment.
Calculator for Styrene
Result
Enter a concentration and an exposure limit to see the
compliant respirators and their Maximum Use Concentration.
Hazard ratio = concentration ÷ OEL · Minimum APF must meet or exceed it · MUC = APF × OEL (capped at IDLH). Source: OSHA 29 CFR 1910.134(d)(3)(i)(A), Table 1 — Assigned Protection Factors. Last verified 2026-07-16.
Maximum use concentration for Styrene by respirator
MUC = APF × the OSHA PEL (100 ppm), capped at the IDLH (700 ppm). Use this as a reference for the highest concentration each respirator class may be used at.
| Respirator | APF | MUC (ppm) |
|---|---|---|
| Air-Purifying Respirator · Quarter mask | 5 | 500 |
| Air-Purifying Respirator · Half mask | 10 | 700IDLH |
| Supplied-Air Respirator (Airline) · Half mask · Demand | 10 | 700IDLH |
| Self-Contained Breathing Apparatus · Half mask · Demand | 10 | 700IDLH |
| Powered Air-Purifying Respirator · Helmet / hood | 25 | 700IDLH |
| Powered Air-Purifying Respirator · Loose-fitting facepiece | 25 | 700IDLH |
| Supplied-Air Respirator (Airline) · Helmet / hood · Continuous flow | 25 | 700IDLH |
| Supplied-Air Respirator (Airline) · Loose-fitting facepiece · Continuous flow | 25 | 700IDLH |
| Air-Purifying Respirator · Full facepiece | 50 | 700IDLH |
| Powered Air-Purifying Respirator · Half mask | 50 | 700IDLH |
| Supplied-Air Respirator (Airline) · Full facepiece · Demand | 50 | 700IDLH |
| Supplied-Air Respirator (Airline) · Half mask · Continuous flow | 50 | 700IDLH |
| Supplied-Air Respirator (Airline) · Half mask · Pressure-demand / positive-pressure | 50 | 700IDLH |
| Self-Contained Breathing Apparatus · Full facepiece · Demand | 50 | 700IDLH |
| Powered Air-Purifying Respirator · Full facepiece | 1,000 | 700IDLH |
| Supplied-Air Respirator (Airline) · Full facepiece · Continuous flow | 1,000 | 700IDLH |
| Supplied-Air Respirator (Airline) · Full facepiece · Pressure-demand / positive-pressure | 1,000 | 700IDLH |
| Self-Contained Breathing Apparatus · Full facepiece · Pressure-demand / positive-pressure | 10,000 | 700IDLH |
Notes
REL TWA 50 ppm (215 mg/m3) ST 100 ppm (425 mg/m3); PEL is a Table Z-2 multi-part limit TWA 100/C 200/600 ppm 5-min peak; IDLH 700 ppm; MW 104.2; conversion 1 ppm = 4.26 mg/m3.
Sources
- https://www.cdc.gov/niosh/npg/npgd0571.html
- https://www.cdc.gov/niosh/idlh/100425.html
- https://www.osha.gov/annotated-pels/table-z-2
Data confidence: high. Values are cited from OSHA and NIOSH but should be verified against the current source and a qualified professional before use. See how this works.