MSA 464031 GMA Organic Vapor Cartridge for Comfo Respirators — Box of 10

MSA GMA Organic Vapor Cartridge Overview

The MSA GMA (SKU 464031) is a NIOSH-approved activated-carbon cartridge that scrubs organic vapors from inhaled air, sold in a 10-pack for $115.50 ($11.55 per cartridge). It threads into the bayonet-style GM-series inlet of MSA Comfo and Ultra-series respirators and provides no particulate filtration — it is a vapor-only cartridge. Workers choosing replacement cartridges for their Comfo platform should start with the respirator cartridge selection guide to confirm this is the right hazard class, then review the filter types explained guide for a side-by-side of vapor vs. combination options. The GMA sits in the broader MSA respirator filters and cartridges collection, which covers all GM-series chemical cartridges and P100 filters.

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Where the MSA GMA Fits in Respirator Selection

Start with the hazard, not the cartridge. The GMA is the correct choice when your SDS or industrial hygienist has confirmed that organic vapors — solvents such as toluene, xylene, acetone, MEK, or similar volatile organic compounds — are the sole respiratory hazard. If your air-monitoring data or SDS also lists particulate exposure (dust, mist, fumes), the GMA/P100 combination cartridge is the correct upgrade; it uses the same bayonet mount and adds NIOSH P100 particulate filtration. If acid gases are part of the hazard profile, step to the MSA GMC OV/acid gas cartridge.

The organic vapor vs. P100 guide walks through the decision tree in detail, and the NIOSH cartridge color chart guide confirms that black = organic vapor per ANSI/ISEA 110.

Who Should Buy the MSA GMA?

Buy the GMA if:

• You already own a Comfo Classic, Comfo II, MSA Ultra-Elite full-face, or Ultra-Twin respirator with GM-series (threaded bayonet) inlets.
• Your air-monitoring data confirms organic vapors as the sole chemical hazard — no particulates, no acid gases, no ammonia.
• You are purchasing in volume (10/pack pricing at $11.55/cartridge) for a maintenance department or spray-paint operation.
• Your environment does not trigger the combination-cartridge threshold (no dual hazards present).

Do not buy the GMA if:

• You need particulate protection — select the GMA/P100 combination cartridge instead.
• You have acid gas exposure — select the GMC OV/acid gas cartridge or GMC/P100 combination.
• You have a multi-gas hazard — select the GME multi-gas cartridge or GME/P100.
• You own an MSA Advantage half-mask — the Advantage series uses a snap-on filter system, not GM bayonet cartridges.
• You own a 3M, Moldex, or Honeywell North respirator — the GM bayonet mount is MSA-specific and not cross-compatible.

What Does the MSA GMA Protect Against?

The GMA uses an activated carbon sorbent bed to adsorb organic vapors. Protection scope is limited to the organic vapor hazard class only.

What the MSA GMA Does NOT Protect Against

• Acid gases (chlorine, SO₂, HCl, HF, hydrogen fluoride) — no impregnated sorbent for acidic species
• Ammonia or methylamine — requires a separate chemisorptive sorbent bed
• Mercury vapor — requires specialized impregnated carbon (Mersorb); see MSA Mersorb/P100 cartridge
• Particulates, dusts, mists, or fumes — no filter media present; the GMA is vapor-only
• Carbon monoxide or other asphyxiants — no SCBA replacement capability
• Iodine or radioactive contaminants — see MSA GMI iodine/P100 cartridge

Best Applications for the MSA GMA

Industrial Painting and Spray Coating

Spray painters working with lacquers, enamels, and solvent-based coatings rely on activated-carbon OV cartridges to reduce solvent vapor exposure below PEL limits. If the spray operation also generates paint mist or particulate overspray, pair with the GMA/P100 combination cartridge. For a broader look at spray paint respirator selection, the cartridge selection guide covers concentration thresholds and ESLI considerations.

Solvent Degreasing and Parts Cleaning

Maintenance technicians using chlorinated or petroleum-based solvents for degreasing operations routinely generate organic vapor concentrations that require half-mask or full-face vapor protection. The GMA fits the MSA Comfo half-mask respirator for routine maintenance tasks where skin and eye exposure do not require full-face coverage.

Chemical Handling and Laboratory Work

Lab technicians and chemical plant operators handling organic reagents (alcohols, ketones, aromatic hydrocarbons) at concentrations below IDLH frequently use OV cartridges for short-duration exposures. Multi-gas environments in chemical plants should be assessed against the GME multi-gas cartridge profile first.

Automotive Refinishing and Body Shop Work

Body shop technicians applying primers, basecoats, and clearcoats encounter isocyanate-containing materials in two-component urethane systems. Note that isocyanate protection requires more than standard OV cartridges — consult your SDS and consider combination cartridges. For pure solvent reducer and thinner work where isocyanates are not present, the GMA covers the organic vapor component on compatible MSA full-face respirators.

Pros and Cons

Compatible MSA Respirators

The GMA uses the MSA GM-series threaded bayonet mount. Verify your respirator's inlet type before ordering.

MSA GMA vs Other MSA GM-Series Cartridges

All cartridges below use the same GM bayonet mount and fit the same MSA Comfo/Ultra respirator platform.

MSA GMA vs MSA GMA/P100 — Head-to-Head

The most common upgrade question for GMA buyers is whether to step to the combination cartridge. Here is the direct comparison.

MSA GMA vs MSA GMC — Organic Vapor vs OV/Acid Gas

MSA GMA Quick Answers

What respirators does the MSA GMA fit?

The MSA GMA cartridge fits all respirators using the GM-series threaded bayonet inlet: the Comfo Classic half-mask, Comfo II half-mask, Ultra-Twin full-face, and Ultra-Elite full-face. It does not fit the MSA Advantage series (which uses snap-on filters) or any non-MSA respirator brand.

Does the GMA filter dust or particulates?

No. The GMA is a vapor-only cartridge with no particulate filter media. It will not filter dust, mist, fumes, or smoke. Workers needing both organic vapor and particulate protection must use the GMA/P100 combination cartridge.

How often should GMA cartridges be replaced?

OSHA 29 CFR 1910.134 requires employers to implement a cartridge change-out schedule based on industrial hygiene data, contaminant concentration, humidity, temperature, and breathing rate. MSA does not publish a universal replacement interval for the GMA because service life varies significantly by exposure conditions. The GMA has no ESLI — use an employer-documented change-out schedule.

Is the GMA NIOSH-approved?

Yes. The GMA is NIOSH-approved for organic vapors under 42 CFR Part 84. The NIOSH approval number is found on the cartridge label and in the MSA Safety published TC approval documentation.

How many cartridges come in a box?

Each box contains 10 GMA cartridges at a list price of $115.50, which works out to $11.55 per cartridge. Full-face respirators require two cartridges per change-out, so a 10-pack provides 5 complete full-face change-outs or 10 half-mask change-outs.

Can I use GMA cartridges for welding fumes?

Welding fumes are primarily particulate (metal oxides) plus potential toxic gas components — they are not an organic vapor hazard. The GMA provides no particulate protection and is not appropriate for welding fume environments. Review the best respirator for welding fumes guide to select the correct cartridge and filter combination.

What is the NIOSH color code for the GMA?

Per ANSI/ISEA 110, organic vapor cartridges are color-coded black. The GMA cartridge body is black, confirming its organic vapor designation at a glance. The NIOSH cartridge color chart guide lists color codes for all hazard classes.

MSA GMA Specifications

Helpful Buying Guides

• How to Choose a Respirator Cartridge — Complete Guide
• Respirator Filter Types Explained — NIOSH P100, OV, AG, Combination
• Organic Vapor vs P100 — When to Use Each
• NIOSH Respirator Cartridge Color Chart Guide
• Best Respirator for Welding Fumes (2026)
• Best Respirator for Silica Dust (2026)

MSA GMA Frequently Asked Questions

Is the GMA the same as the MSA 464031?

Yes. SKU 464031 is MSA's part number for the GMA Organic Vapor Cartridge sold in a box of 10. The "GMA" model designation refers to the cartridge type; 464031 is the inventory SKU used on purchase orders, safety data sheets, and compliance documentation.

Will the GMA work on an MSA Advantage respirator?

No. The MSA Advantage series — including the Advantage 200 LS, 420, and 900 — uses a proprietary snap-on filter attachment system that is mechanically incompatible with GM bayonet cartridges. Using a GMA cartridge on an Advantage respirator is not possible and not approved by MSA. Use only Advantage-rated snap-on filters on Advantage respirators.

Can the GMA be used for spray painting?

Only if the spray operation generates organic vapors with no paint mist or particulate overspray. In virtually all spray-paint applications, airborne paint mist is also present — that requires a combination cartridge. The GMA/P100 combination cartridge is the correct choice for spray painting because it covers both the vapor and the particulate components simultaneously.

Does this cartridge protect against chlorine gas?

No. Chlorine is an acid gas, and the GMA is not rated or approved for acid gas protection. Chlorine exposure requires an acid-gas-rated cartridge such as the GMB acid gas cartridge. If both organic vapors and chlorine are present, use the GMC OV/acid gas combination cartridge.

How do I know when to replace GMA cartridges?

MSA does not include an ESLI on the GMA. OSHA 29 CFR 1910.134(d)(3)(iii)(B)(1) requires an employer-developed change-out schedule based on documented industrial hygiene data. The schedule must account for contaminant type, concentration, humidity, temperature, and work duration. NIOSH provides a free cartridge change-out schedule calculator at cdc.gov/niosh as a starting reference.

Are GMA cartridges approved for use in confined spaces?

Air-purifying cartridge respirators are generally not permitted in permit-required confined spaces per OSHA 29 CFR 1910.146 unless continuous atmospheric monitoring confirms conditions remain non-IDLH and oxygen is 19.5%–23.5%. Most permit-required confined space entries require supplied-air respirators or SCBA. Consult your site's confined-space entry program before using any APR in a confined space.

What is the shelf life of unopened GMA cartridges?

MSA publishes shelf-life guidance in their product documentation; activated-carbon cartridges should be stored in their original sealed packaging in a cool, dry location away from chemical vapors. Consult MSA Safety's published product data or contact MSA technical support for the specific shelf-life statement applicable to lot number on your packaging.

Can I pair the GMA with an MSA P100 snap-on pre-filter for combination protection?

No. The GMA bayonet cartridge and the MSA Advantage snap-on pre-filter system are not designed to combine together. The correct solution for OV + particulate protection on the Comfo/Ultra platform is the purpose-built GMA/P100 combination cartridge, which integrates both media in a single unit engineered and NIOSH-approved as a combination device.

Does the GMA protect against formaldehyde?

Formaldehyde is a Class A organic vapor per NIOSH definitions, but standard OV cartridges have variable and typically limited efficiency against formaldehyde because its boiling point and carbon affinity differ from most solvents. For confirmed formaldehyde exposure, consult the SDS and MSA technical guidance — a specifically formaldehyde-rated or combination cartridge may be required depending on concentration.

Is buying a 10-pack more economical than buying cartridges individually?

The GMA is sold exclusively as a 10-pack (SKU 464031) at this listing. The $11.55 per-cartridge price on the 10-pack is the standard unit cost for this product. For maintenance departments or operations replacing cartridges on a regular schedule, the 10-pack format reduces per-unit cost compared to single-pair alternatives from other product lines.

Can one 10-pack supply a crew of workers?

A 10-pack provides 10 cartridges. On half-mask respirators (1 cartridge per side = 2 per change-out), a 10-pack supports 5 complete cartridge change-outs. On full-face respirators like the Ultra-Elite or Ultra-Twin (2 cartridges per change-out), the same logic applies — 5 full change-outs per 10-pack. For multi-person crews on daily or weekly change-out schedules, order quantities should be calculated based on crew size and change-out frequency per your respiratory protection program.

How does the GMA compare to 3M or Moldex organic vapor cartridges?

All NIOSH-approved OV cartridges use activated carbon and meet the same Part 84 organic vapor standard regardless of brand. The key difference is the mount system — the GMA uses MSA's GM bayonet, which is not compatible with 3M, Moldex, or Honeywell North respirators. If you own a 3M respirator, the equivalent vapor cartridge is the 3M 6001. If you own a Moldex respirator, the equivalent is found in the Moldex cartridges collection. Never mix cartridge brands across respirator platforms.