Respirators for Acid Gases

The exposure limits

What the federal rule says

Each entry is condensed from the paragraph cited; the paragraph itself is the rule and the link opens it.

29 CFR 1910.134(d)(3)(iii)(B): For gases and vapors: an atmosphere-supplying respirator, or an air-purifying respirator with a NIOSH-certified ESLI for the contaminant, or a cartridge change schedule based on objective data.

29 CFR 1910.134(d)(2): In IDLH atmospheres the employer shall provide a full facepiece pressure demand SCBA certified by NIOSH for a minimum service life of thirty minutes, or a combination full facepiece pressure demand supplied-air respirator with auxiliary self-contained air supply.

Source: 29 CFR, Occupational Safety and Health Standards, as published by OSHA (ecfr.gov / osha.gov), read Nov 2–3 2026.

California (Cal/OSHA)

Each entry is condensed from the paragraph cited; the paragraph itself is the rule and the link opens it.

Title 8 §5144(d): Cal/OSHA carries the same selection rules.

Source: California Code of Regulations, Title 8, as published by Cal/OSHA (dir.ca.gov), read Nov 2–3 2026.

What the makers' data lists for acid gases

The North chart defines acid gas as chlorine, hydrogen chloride, sulfur dioxide, hydrogen fluoride and chlorine dioxide (N75002L also formaldehyde); Dräger's AG filters are coded OV/AG/HF/FM/CD (6738025) and the PAPR OV/AG/HE (6739565). The manufacturer states the North 7583P100L can be used with hydrochloric acid only at exposures under 50 ppm (support article 000022746).

North cartridges and filters whose chart entry covers it

Source: North Cartridge & Filter Reference Chart; NIOSH approval labels (PIP).

North facepieces

Source: North product sheets (PIP).

Dräger filters listed for it

Source: Dräger Guide for Selection and Use of Respiratory Filtering Devices, NIOSH (DMC-104642); Dräger X-plore Bayonet Filters NIOSH product information (DMC-109824); Dräger X-plore 8000 product information (DMC-102510).

Dräger masks

Source: Dräger Product Catalog, Industrial Applications (DMC-107423).

Dräger X-plore 8000 PAPR blowers

Source: Dräger X-plore 8000 product information (DMC-102510).

Dräger selection guide entries

4 entries in the Dräger respiratory selection guide match acid gases; each names the filters by part number.

Source: Dräger Respiratory Protection Selection Guide (PIP document library).

Assigned protection factor

Source: OSHA 29 CFR 1910.134 Table 1 (Assigned Protection Factors). The APF applies only when the respirator is used in a program that meets the standard, including fit testing of tight-fitting facepieces (29 CFR 1910.134(f)) and a cartridge change schedule (29 CFR 1910.134(d)(3)(iii)).

Guides: half mask vs full facepiece · assigned protection factors · cartridge change schedules · P100 vs N95 vs R95 · what OSHA requires for fit testing · cleaning and storing respirators.

Respirators for Acid Gases questions

What does an acid gas cartridge cover? On the North chart: chlorine, hydrogen chloride, sulfur dioxide, hydrogen fluoride and chlorine dioxide (white label N75002L adds formaldehyde). Dräger's AG code on the bayonet filters is listed with OV, HF, FM and CD.

What is the white cartridge? North N75002L, acid gas and formaldehyde (white label); 7582P100L is the same with a P100 filter (white and magenta).