3M 6004 Review: Ammonia & Methylamine Respirator Cartridge

Quick Verdict

The 3M 6004 is a specialty single-class cartridge for one job: ammonia and methylamine gas. It carries the green NIOSH band and is gas-only, with no particulate filter. If you work around anhydrous ammonia refrigeration, wastewater systems, or fertilizer, this is the focused, correct cartridge — there are very few half-mask alternatives that cover ammonia at all.

Who should not choose it: anyone whose hazard is solvent vapor, acid gas, formaldehyde, dust, or welding fume. The 6004 does nothing for those. It is also not an emergency device — a real ammonia release is an IDLH event that requires supplied air or SCBA, never an air-purifying cartridge.

The closest alternative is the 3M 60924, which adds a built-in P100 filter for particulate; the broader option is the multi-gas 3M 6006, which covers ammonia plus several other gas classes. New to cartridge classes? Start with how to choose a respirator cartridge and the ammonia cartridge guide.

What the 3M 6004 Is Designed For

The 6004's protection category is ammonia and methylamine (AM/MA) only. Its sorbent is tuned to capture these alkaline gases — a different chemistry from the activated carbon in an organic vapor cartridge — which is why ammonia needs its own dedicated cartridge rather than a general-purpose one. The green band is the NIOSH signal for ammonia/methylamine.

Intended applications are the workplaces where ammonia is the defining hazard: industrial refrigeration and cold storage (anhydrous ammonia is a common refrigerant), water and wastewater treatment, agriculture and fertilizer handling, and chemical processes that release ammonia or methylamine. In the 3M lineup the 6004 is a specialty branch, separate from the organic-vapor ladder (6001 / 6003 / 6006) — you reach for it specifically when ammonia is on the SDS. For the family overview, see the 3M respirator cartridge guide and the cartridge color chart.

Key Specifications

Real-World Use Cases

The 6004 is a focused tool. These are the settings where it is the right cartridge:

• Industrial refrigeration & cold storage: facilities running anhydrous ammonia (R-717) for routine maintenance and monitoring tasks within exposure limits.
• Water & wastewater treatment: ammonia handling and dosing areas where ammonia gas is the inhalation hazard.
• Agriculture & fertilizer: anhydrous ammonia application and storage, livestock and poultry operations with elevated ammonia.
• Chemical manufacturing & handling: processes that release ammonia or methylamine, and transfer/decanting tasks within the cartridge's limits.
• Cleaning & sanitation: concentrated ammonia-based cleaning in enclosed areas where vapor builds up.

Note what is absent from this list: painting, solvents, and dust. Those are different hazard classes — if they are present alongside ammonia, you need a combination or multi-gas cartridge, not the single-class 6004.

What This Cartridge Does Well

• Fills a real gap: ammonia is one of the few gases most general cartridges do not touch — the 6004 is the dedicated, NIOSH-approved answer.
• Simple selection: one hazard, one cartridge; if the SDS says ammonia/methylamine and nothing else, the choice is clear.
• Low breathing resistance: as a gas-only cartridge it has no particulate media, so airflow stays comfortable on long shifts.
• Broad respirator compatibility: the same cartridge fits every current 3M bayonet half mask and full facepiece.
• Clear upgrade path: when particulate or extra gases appear, you move to the 60924 or 6006 without changing your facepiece or re-fit-testing.

Where the 3M 6004 Is Not the Right Choice

This section matters most for a specialty cartridge. The 6004 is the wrong choice when:

• Particulate is in the air. Dust, mist, or aerosol need a P100 — use the ammonia + P100 60924, or read the 3M 60924 review.
• Multiple gas classes are present. Ammonia plus organic vapor, acid gas, or formaldehyde calls for the multi-gas 6006 (or 60926 with P100). The gas-class logic is in organic vapor vs multi-gas cartridge.
• Your hazard is formaldehyde. That is a different specialty — see the 6005 and the formaldehyde cartridge guide.
• The atmosphere is IDLH, oxygen-deficient, or unknown. An ammonia release is an emergency that requires supplied air or SCBA — no cartridge, including the 6004, is appropriate.

3M 6004 vs Similar 3M Cartridges

Because ammonia coverage is rare, the 6004's "competitors" are mostly its own combination and multi-gas siblings:

For the detailed pairings, read the 3M 6006 multi-gas review and the 3M 60926 review.

Compatible Respirators

The 6004 uses the standard 3M bayonet connection and seats on the full current range of 3M bayonet facepieces:

• 3M 6000 Series half masks (6100/6200/6300) — the economical everyday option.
• 3M 6500QL Series (Rugged Comfort, quick-latch) — for plant and treatment-facility work.
• 3M 7500 Series (silicone, all-day comfort) — the most comfortable half-mask pairing for long shifts.
• 3M 6000 Series full facepieces (6700/6800/6900) — APF 50 with eye protection, useful since ammonia irritates the eyes.
• 3M 7800S Series full facepieces (premium silicone full face).

It does not fit the 3M Secure Click line (a different mount) or any non-3M facepiece — cartridge mounts are brand-specific. See are respirator cartridges universal?

Who Should Buy This Cartridge?

• Refrigeration and cold-storage technicians working around anhydrous ammonia systems who need dedicated ammonia protection for routine tasks.
• Water and wastewater operators handling ammonia dosing and treatment where ammonia gas is the hazard.
• Agricultural and fertilizer handlers exposed to ammonia in storage, application, or livestock environments.
• Not the right choice for painting, solvents, acid gas, formaldehyde, dust, or welding — and never for an ammonia leak/IDLH event, which requires supplied air or SCBA.

Final Recommendation

The 3M 6004 is the right cartridge for one clearly defined hazard: ammonia or methylamine gas. Within that lane it is the focused, NIOSH-approved choice, and it fills a gap that general-purpose cartridges simply do not cover. Buy it when the SDS lists ammonia/methylamine and nothing else, and pair it with whichever 3M facepiece fits your crew — a full facepiece is worth considering since ammonia irritates the eyes.

The closest alternative is the 60924 when particulate is also present; the broader upgrade for mixed gases is the 6006 (or the 60926 with P100). Still deciding? Use how to choose a respirator cartridge, the ammonia cartridge guide, and browse all 3M respirator cartridges and filters.

Frequently Asked Questions