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respiratorcalc

Respirator selection

Xylenes (o-, m-, p-isomers) respirator selectionC8H10

General-purpose solvent in paints, coatings, adhesives, printing; chemical intermediate (phthalic anhydride, PET). Coatings, printing, petrochemicals.

OSHA PEL
100 ppm
TWA 8-hr (Table Z-1; ~435 mg/m3)
NIOSH REL
100 ppm
TWA (also STEL 150 ppm)
IDLH
900 ppm
Molecular weight
106.2 g/mol

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 xylenes (o-, m-, p-isomers). Adequate warning properties; standard OV cartridge is effective up to the maximum use concentration. IDLH 900 ppm. You must establish a change-out schedule; never rely on taste or smell. See the cartridge & filter guide.

⚠ Skin absorption hazard: a respirator alone is not enough

Xylenes carry a NIOSH "skin" notation and are absorbed through the skin, so skin protection is required in addition to a respirator. Wear chemical-protective gloves and clothing rated for this substance, plus eye and face protection. Flame-resistant (FR) clothing guards against flash fire, not chemical permeation, so it is not a substitute for a chemical-protective suit.

⚠ Skin absorption hazard: a respirator alone is not enough

Xylenes carry a NIOSH "skin" notation and are absorbed through the skin, so skin protection is required in addition to a respirator. Choose gloves and protective clothing rated against this chemical (check the Safety Data Sheet for permeation data), and use eye protection.

Calculator for Xylenes (o-, m-, p-isomers)

Inputs

Xylenes (o-, m-, p-isomers) exposure

Unit
ppm

This is the measured airborne level from air monitoring / an exposure assessment by a qualified person — not a guess. No sampling data yet? See how to get an exposure concentration.

ppm

Presets fill the OSHA PEL. Many IH programs use the most protective of the OSHA PEL, NIOSH REL, or ACGIH TLV — enter whichever limit you use and the calculator applies it.

ppm

Enter molecular weight to convert values when you switch between ppm and mg/m³.

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 Xylenes (o-, m-, p-isomers) by respirator

MUC = APF × the OSHA PEL (100 ppm), capped at the IDLH (900 ppm). Use this as a reference for the highest concentration each respirator class may be used at.

RespiratorAPFMUC (ppm)
Air-Purifying Respirator · Quarter mask5500
Air-Purifying Respirator · Half mask10900IDLH
Supplied-Air Respirator (Airline) · Half mask · Demand10900IDLH
Self-Contained Breathing Apparatus · Half mask · Demand10900IDLH
Powered Air-Purifying Respirator · Helmet / hood25900IDLH
Powered Air-Purifying Respirator · Loose-fitting facepiece25900IDLH
Supplied-Air Respirator (Airline) · Helmet / hood · Continuous flow25900IDLH
Supplied-Air Respirator (Airline) · Loose-fitting facepiece · Continuous flow25900IDLH
Air-Purifying Respirator · Full facepiece50900IDLH
Powered Air-Purifying Respirator · Half mask50900IDLH
Supplied-Air Respirator (Airline) · Full facepiece · Demand50900IDLH
Supplied-Air Respirator (Airline) · Half mask · Continuous flow50900IDLH
Supplied-Air Respirator (Airline) · Half mask · Pressure-demand / positive-pressure50900IDLH
Self-Contained Breathing Apparatus · Full facepiece · Demand50900IDLH
Powered Air-Purifying Respirator · Full facepiece1,000900IDLH
Supplied-Air Respirator (Airline) · Full facepiece · Continuous flow1,000900IDLH
Supplied-Air Respirator (Airline) · Full facepiece · Pressure-demand / positive-pressure1,000900IDLH
Self-Contained Breathing Apparatus · Full facepiece · Pressure-demand / positive-pressure10,000900IDLH

Notes

All three isomers: REL TWA 100 ppm (435 mg/m3) ST 150 ppm (655 mg/m3); PEL TWA 100 ppm; IDLH 900 ppm; MW 106.2. Per-isomer ppm to mg/m3 conversion differs: o-/m- = 4.34, p- = 4.41 (genuine NPG rounding quirk). Mixed-xylenes CAS 1330-20-7. OSHA Z-1 has TWA only; the 150 ppm STEL is the NIOSH value.

Sources

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.

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