MSA 815179 GMB-P100 Acid Gas / P100 Cartridge for Comfo Respirators — Box of 6

MSA GMB-P100 Overview

The MSA GMB-P100 Acid Gas / P100 Cartridge (MSA part 815179) is a NIOSH-approved combination cartridge that pairs an impregnated acid gas sorbent bed with a P100 particulate filter rated at 99.97% efficiency — sold as a box of 6 for $218.22 ($36.37 per cartridge). It mounts on MSA Comfo-platform half-masks via the proprietary bayonet fitting and is NIOSH-approved under 42 CFR Part 84 for combined acid gas and P100 particulate service.

Buyers evaluating this cartridge against the broader MSA Comfo lineup should also review the MSA Respirator Filters & Cartridges collection and consult the respirator filter types guide to confirm the hazard class match before ordering.

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Where the GMB-P100 Fits in Respirator Selection

Start with hazard confirmation: the GMB-P100 belongs in your cart only if your safety data sheet identifies an acid gas as the primary chemical hazard — chlorine, hydrogen chloride, sulfur dioxide, hydrogen fluoride, or similar inorganic acid vapors — and your exposure environment also generates respirable particulate. If your SDS calls out organic solvents, the cartridge lacks the activated carbon bed needed for organic vapor service; the MSA GMC-P100 covers both hazard classes in a single cartridge.

The P100 layer addresses any co-existing fine particulate: silica dust, metal fumes, weld smoke, or acid mist aerosols. For pure acid gas exposures without meaningful particulate, the cartridge-only MSA GMB Acid Gas Cartridge costs less per unit. Understand the full decision tree by reading the respirator cartridge selection guide and the cartridge color-code chart before finalizing your PPE order.

Who Should Buy the GMB-P100?

Buy the GMB-P100 if:

• Your job involves chlorine, HCl, SO₂, HF, or other acid gases alongside respirable dust or fumes
• You already own a Comfo Classic, Comfo II, or Advantage 200 LS half-mask and need a replacement dual-purpose cartridge
• Your facility uses MSA Comfo respirators site-wide and you need cartridges that slot into existing inventory without introducing a new mount type
• You need NIOSH 42 CFR Part 84 documentation for compliance recordkeeping
• You are purchasing for water treatment, battery cell maintenance, or chemical lab decanting operations

Do not buy the GMB-P100 if:

• Your primary hazard is an organic solvent or vapor — choose the MSA GMA-P100 instead
• You face both organic vapor and acid gas simultaneously — the MSA GMC-P100 is the correct selection
• Your respirator uses 3M bayonet, Moldex thread, or Honeywell North bayonet fittings — this cartridge uses the MSA Comfo bayonet only
• Your hazard assessment identifies ammonia or methylamine — use the MSA GMD-P100
• You need multigas protection across four or more hazard classes — evaluate the MSA GME-P100

What Does the GMB-P100 Protect Against?

What the GMB-P100 Does NOT Protect Against

• Organic vapors (solvents, paints, fuels) — no activated carbon bed in this cartridge
• Ammonia and methylamine — requires the MSA GMD-P100
• Mercury vapor — requires the MSA MERSORB-P100
• Carbon monoxide and other gases without acid gas character
• Radioactive particulate beyond standard P100 filtration efficiency claims
• Chemical warfare agents — not rated for CBRN service

Best Applications for the GMB-P100

Water Treatment and Chlorination

Chlorine gas is the dominant inhalation hazard in water treatment plant operations — dosing, breakpoint chlorination, and system maintenance all generate acid gas exposures at varying concentrations. The GMB-P100's acid gas sorbent addresses the chemical vapor component while the P100 layer intercepts chlorine mist aerosol and any co-existing particulate from pipe scale or sediment. Operators at municipal and industrial water treatment facilities who run Comfo Classic or Comfo II respirators can use this cartridge as a direct stock replacement.

Battery Manufacturing and Maintenance

Lead-acid battery manufacturing, cell formation, and maintenance produce sulfuric acid mist, hydrogen gas, and fine lead-oxide particulate simultaneously. The GMB-P100 captures sulfuric acid vapor through the acid gas sorbent and battery acid aerosol mist plus lead particulate through the P100 filter layer — covering the two primary inhalation vectors in a single cartridge. Consult the guide to respirators for metal fume environments for context on P100 performance with metal particulate.

Chemical Processing and Laboratory Decanting

HCl, H₂SO₄, and HF are common reagents in semiconductor fabrication, pharmaceutical synthesis, and general chemical manufacturing. Decanting, dilution, or transfer operations generate both vapor and aerosol exposure. Workers performing these tasks under existing Comfo respirator programs will find the GMB-P100 a compliant, single-unit solution that does not require switching to a different respirator platform. Pair with the cartridge selection decision guide to validate against your specific SDS data.

Metal Surface Finishing and Plating

Acid pickling baths (hydrochloric acid, sulfuric acid) and electroplating tanks emit acid vapors and fine metallic aerosols. The P100 layer handles chromium mist, nickel particulate, and bath aerosol; the acid gas bed addresses HCl and SO₂ vapor. Browse the full MSA full-face respirator collection if your exposure assessment calls for a higher assigned protection factor than a half-mask provides.

GMB-P100 Pros and Cons

Compatible MSA Respirators

The GMB-P100 uses the MSA Comfo bayonet mount. The following table lists confirmed compatible and incompatible MSA respirator models.

Always verify compatibility against your specific respirator model and lot documentation. Browse compatible MSA half-mask respirators or MSA full-face respirators if you are also sourcing the facepiece.

GMB-P100 vs Other MSA Comfo Combination Cartridges

GMB-P100 vs MSA GMB (Acid Gas Only)

The MSA GMB and the GMB-P100 both target acid gas hazards on the Comfo platform. The critical differentiator is the P100 particulate filter layer:

GMB-P100 vs MSA GMC-P100 (OV + Acid Gas + P100)

The MSA GMC-P100 is the most common upgrade path when workers face both organic solvent vapors and acid gases in the same environment:

Compare available 3M respirator cartridges or Moldex respirator cartridges if your facility is not committed to the MSA Comfo platform.

GMB-P100 Quick Answers

What respirators does the MSA GMB-P100 fit?

The MSA GMB-P100 fits MSA Comfo-platform half-masks that use the proprietary Comfo bayonet mount: the Comfo Classic (Hycar and Silicone versions), the Comfo II, and the Advantage 200 LS. It does not fit MSA Ultra-Twin, Ultra-Elite, or Advantage full-face respirators, which use different cartridge attachment systems.

Is the GMB-P100 NIOSH-approved?

Yes. The MSA GMB-P100 is NIOSH-approved under 42 CFR Part 84 for combined acid gas and P100 particulate service. The P100 rating certifies a minimum 99.97% filtration efficiency against oil and non-oil-based aerosols. NIOSH approval documentation is available from MSA Safety for compliance recordkeeping purposes.

How many cartridges are in a box and what does each cost?

Each box contains 6 cartridges at a list price of $218.22, which works out to approximately $36.37 per cartridge. The cartridges are sold in pairs — two per respirator — so one box outfits three complete respirator setups.

Does the GMB-P100 protect against chlorine gas?

Yes. Chlorine (Cl₂) is classified as an acid gas and falls within the GMB-P100's NIOSH-rated protection scope. The acid gas sorbent bed adsorbs chlorine vapor while the P100 filter layer captures any chlorine mist aerosol. This makes the cartridge a standard choice for water treatment plant operations and chlorination system maintenance. Consult your IH for service life determination.

Can I use the GMB-P100 for organic vapor exposures?

No. The GMB-P100 contains an acid gas sorbent bed and a P100 filter — it has no activated carbon layer for organic vapor adsorption. Workers exposed to solvents, paints, fuels, or other organic compounds need the MSA GMA-P100 (OV only) or the MSA GMC-P100 (OV + acid gas). See the organic vapor vs P100 guide for a full comparison of these protection classes.

How do I know when to change the GMB-P100 cartridge?

The GMB-P100 does not include an ESLI (end-of-service-life indicator). Under OSHA 29 CFR 1910.134(d)(3)(iii)(B), facilities must implement a documented cartridge change schedule based on objective data — industrial hygiene air monitoring, manufacturer service life charts, or published exposure modeling. Replace cartridges immediately if odor, taste, or irritation is detected through the facepiece, or per your facility's established change interval, whichever comes first.

Is the MSA Comfo bayonet compatible with 3M or Moldex respirators?

No. The MSA Comfo bayonet mount is proprietary to the MSA Comfo respirator platform and is not interchangeable with 3M bayonet cartridges, Moldex threaded cartridges, or Honeywell North bayonet systems. Cross-brand cartridge use is not permitted — always confirm mount compatibility before purchasing replacement cartridges.

MSA GMB-P100 Specifications

Helpful Buying Guides

• How to Choose a Respirator Cartridge — Complete Selection Guide
• Respirator Filter Types Explained: P100, P95, R95, N95 and Chemical Classes
• Respirator Cartridge Color Chart — NIOSH Color Code Reference
• Organic Vapor vs P100: Which Respirator Cartridge Do You Need?
• Best Respirator for Silica Dust (2026) — P100 and Half-Mask Selection
• Best Respirator for Welding Fumes — Filter and Cartridge Guide
• 3M Respirator Filter and Cartridge Guide — Cross-Reference and Selection

MSA GMB-P100 Frequently Asked Questions

Does the GMB-P100 work with the MSA Comfo Classic respirator?

Yes. The GMB-P100 is designed specifically for the MSA Comfo platform and mounts directly on the Comfo Classic in both the Hycar and Silicone rubber variants. The Comfo bayonet fitting provides a positive-lock connection. Verify your specific respirator model number against MSA's compatibility chart before placing a bulk order.

What is the difference between the GMB and GMB-P100?

Both cartridges protect against acid gases on the MSA Comfo platform, but the GMB-P100 adds a P100 particulate filter layer rated at 99.97% efficiency. The base GMB cartridge is an acid-gas-only cartridge suitable for environments with no significant airborne particulate. The GMB-P100 is required when your exposure assessment identifies both acid gas vapors and respirable dust, metal fumes, or mist aerosols in the same work area.

Can the GMB-P100 be used for hydrogen sulfide (H₂S)?

Hydrogen sulfide is classified as an acid gas, but standard acid gas cartridges provide limited capacity for H₂S and are not reliably rated for it at high concentrations. MSA's published specifications for the GMB-P100 target chlorine, HCl, SO₂, and HF. For H₂S-specific applications, consult your industrial hygienist and review the MSA GME or GME-P100 multigas cartridges, or contact MSA Safety directly for service life data.

How many GMB-P100 cartridges does one respirator require?

Half-mask respirators such as the Comfo Classic and Comfo II use two cartridges simultaneously — one on each side of the facepiece. A single box of 6 GMB-P100 cartridges supplies three complete cartridge changes for one respirator. For a five-person crew, you would need approximately four boxes to support one full cartridge change per worker.

Is the GMB-P100 approved for use in confined spaces?

Air-purifying respirators are not approved for confined space entry where oxygen deficiency or IDLH concentrations may exist. Confined space entry that falls under OSHA permit-required confined space regulations (29 CFR 1910.146) typically demands atmospheric testing and, where hazardous atmospheres are present, supplied-air equipment. The GMB-P100 may be used for routine above-entry work in acid gas environments but is not a substitute for SCBA in permit-required confined spaces.

What is the shelf life of the MSA GMB-P100 cartridge?

MSA Safety publishes shelf life data for Comfo series cartridges in their product documentation. Generally, sealed respirator cartridges remain serviceable for five years from the date of manufacture when stored in cool, dry conditions away from direct sunlight and chemical contaminants. Check the lot number and manufacturing date on your specific carton and reference MSA's current shelf life guidance for confirmed figures.

Does the P100 rating on the GMB-P100 cover oil-based aerosols?

Yes. The P-class designation in NIOSH's 42 CFR Part 84 rating system indicates that the filter is resistant to oil aerosols — P stands for "P100 oil-proof" filtration efficiency. This makes the GMB-P100 suitable for environments with both acid gas vapors and oil-based mists or aerosols, unlike N-class (not oil-resistant) or R-class (oil-resistant, single shift only) filter options.

Can I use the GMB-P100 on a 3M or Honeywell North respirator?

No. The GMB-P100 uses the proprietary MSA Comfo bayonet mount, which is not compatible with 3M bayonet, Honeywell North bayonet, or Moldex threaded connection systems. Attempting to force-fit incompatible cartridges creates a seal failure risk and is a violation of NIOSH approval conditions. Buyers on 3M platforms should review 3M respirator cartridges; buyers on Moldex platforms should review Moldex respirator cartridges.

What color is the MSA GMB-P100 cartridge?

NIOSH assigns color codes to help identify cartridge types: acid gas cartridges carry a white color band, and combination cartridges with P100 particulate protection typically display the characteristic magenta/purple P100 indicator. The GMB-P100 combines these designations per NIOSH color-coding conventions. See the full cartridge color-code chart for a complete reference across all hazard classes.

Is the GMB-P100 suitable for chlorine bleach odors in a janitorial setting?

Low-concentration incidental exposure to bleach vapors in well-ventilated commercial cleaning environments typically does not require respiratory protection beyond engineering controls and good practice. The GMB-P100 is an industrial cartridge rated for meaningful acid gas concentrations. If a facility's IH assessment confirms chlorine levels that require respiratory protection, the GMB-P100 on a properly fitted Comfo respirator is an appropriate choice — but cartridge selection must be driven by air monitoring data, not convenience.

What is the assigned protection factor for a half-mask with the GMB-P100?

OSHA 29 CFR 1910.134 Table 1 assigns a protection factor of 10 (APF 10) to all negative-pressure half-mask air-purifying respirators, including Comfo Classic and Comfo II configurations with the GMB-P100. This means the half-mask reduces inhaled concentration to 1/10th of the ambient level, up to 10× the permissible exposure limit. Workers in atmospheres exceeding 10× the PEL require a full-face respirator with an APF of 50.

Are there P100-only filter options for Comfo respirators if I don't need acid gas protection?

Yes. MSA offers the MSA Low Profile P100 Particulate Filter for Comfo respirators where the hazard is particulate only — no chemical gas or vapor component. This option provides P100 protection at lower cartridge weight and breathing resistance than the combined GMB-P100. Choose the GMB-P100 only when acid gas protection is confirmed necessary by your exposure assessment.