Respirator Filters and Cartridges

NIOSH 42 CFR 84 Classes · P100 · Organic Vapor · Acid Gas · Multi-Gas · Bayonet & Threaded Fits

Which respirator filters and cartridges should you buy in 2026?

Short answer: If your hazard is dust, mist, or metal fume, a P100 particulate filter like the 3M 2091 covers it. If you are working with solvents, paints, or adhesives, you need a gas and vapor cartridge such as the 3M 6001 organic vapor. Facing both at once — spray painting, for example — use a combination unit like the 3M 60921, which stacks P100 particulate onto an organic vapor bed. Every unit here states its NIOSH approval on the manufacturer's listing.

VIEW THE 3M 2091 P100 →CHECK PRICE ON AMAZON →

Editor's pick: the 3M 60921 — for mixed-exposure work it eliminates the stacking mistakes that cause most of the fit and compatibility problems we see reported.

Affiliate disclosure: WC Safety is an independent review site. As an Amazon Associate we earn from qualifying purchases made through links on this page, at no extra cost to you. We do not sell products directly, and no brand paid for placement.

Our methodology: how this collection was curated

Respiratory protection is life-safety equipment, so the screen is strict. Every filter and cartridge here must carry a NIOSH approval stated on the manufacturer's listing, with its class, service-life indicator status, and — critically — its facepiece compatibility and attachment method documented. We verify attachment claims against the manufacturer's own compatibility tables rather than inferring them from appearance, because a filter that physically touches a facepiece is not the same as a filter approved for it. We never publish our own breakthrough times or change schedules; those come from the maker's software or your own objective data under OSHA rules. Anything we cannot trace to manufacturer documentation is excluded.

Respirator Filters and Cartridges (2026)

The distinction that governs this entire category: filters capture particles, cartridges adsorb gases and vapors. A P100 will not protect you from solvent vapor, and an organic vapor cartridge will not stop welding fume. NIOSH certifies both under 42 CFR Part 84, and OSHA 29 CFR 1910.134 requires that any workplace using them run a written respiratory protection program covering hazard assessment, medical evaluation, fit testing, and cartridge change schedules. This collection inside our respiratory silo covers particulate filters, gas and vapor cartridges, combination units, and pre-filters across 3M, Honeywell North, MSA, Moldex, GVS, and Miller. Not sure what you need? Start with the respirator cartridge selector.

What this collection covers

• P100 particulate filters — the 3M 2091 and slimmer 2291, plus nuisance-relief variants: the 2097 (organic vapor) and 2096 (acid gas).
• Gas and vapor cartridges — 6001 organic vapor, 6003 OV/AG, and 6006 multi-gas.
• Combination P100 filter cartridge units — 60921, 60923, and 60926 stack particulate protection onto a chemical bed.
• Pre-filters and retainers — the 5N11 N95 and 5P71 P95 pre-filters, which need the 501 retainer cap to mount. See the retainer rule below.

Shopping by brand? Go to 3M, Honeywell North, MSA, or Moldex. Shopping by class? Try P100 filters or N95 filters.

Filter and cartridge class comparison

Shop by brand / platform: 3M · Honeywell North · MSA · Moldex · PAPR filters

Shop by filter class / hazard: P100 particulate · Organic vapor · Combination · Acid gas · N95 filters

Shop cartridges & filters on Amazon →3M 2091 P1003M 6001 OV3M 60921 OV/P1003M 60926 multi-gas

How to choose respirator filters and cartridges

Filter or cartridge — which does your hazard need?

Identify the contaminant first, because the two families do different physics. Particulate filters mechanically trap solid and liquid aerosols: dust, welding fume, lead, asbestos, paint overspray. Gas and vapor cartridges use a sorbent bed that chemically adsorbs molecules too small for any filter to catch. Solvents, chlorine, ammonia, and formaldehyde all pass straight through a P100. When your task produces both — spraying solvent-based paint is the classic case — a combination unit handles them together: a P100 cartridge layers particulate media over the sorbent bed, so one part covers both hazard classes.

What do N, R, and P actually mean?

They describe oil resistance, not efficiency. N is not resistant to oil aerosols, R is somewhat resistant with a limited service time, and P is oil proof. The number that follows is filtration efficiency against the test aerosol: 95, 99, or 99.97 percent for the class labelled 100. So a P100 filter is oil-proof and 99.97 percent efficient, which is why it is the default for lead, asbestos, and metal fume work. Worth stating plainly: there is no such thing as a P200 — the NIOSH scheme under 42 CFR Part 84 stops at 100, and any listing advertising one is describing something that does not exist.

The retainer rule: which filters need the 501 cap?

This is the single most common ordering mistake in the category, and it is worth getting right before you check out. The 3M 2000-series filters — the 2091, 2096, 2097, and 2291 — attach directly to a compatible bayonet facepiece; they need no accessory. The 5N11 and 5P71 pre-filters do not: they are flat pads that require the 501 retainer cap to hold them against a cartridge. Ordering 5N11 pads without the 501 leaves you with filters you physically cannot mount. Check your facepiece's compatibility table on the manufacturer's listing before ordering either way.

How do you know when to change a cartridge?

Not by smell. Relying on odor breakthrough means you were already breathing the contaminant, and some chemicals have poor warning properties or deaden the sense of smell entirely. OSHA 1910.134 requires gas and vapor cartridges to be changed on a schedule based on objective data or an end-of-service-life indicator — most manufacturers publish software that calculates this from your contaminant, concentration, humidity, and work rate. Particulate filters are different: replace them when breathing resistance rises noticeably, or when damaged or soiled. Our guide on how long respirator cartridges last covers the calculation, and cartridge shelf life covers unopened storage.

Regulatory context: NIOSH approval and the OSHA program

NIOSH certifies respirator components under 42 CFR Part 84, and an approval covers a specific assembly — facepiece plus filter or cartridge — not a part in isolation. Mixing a filter from one maker onto another maker's facepiece voids the approval even when the parts appear to fit, which is why we publish attachment compatibility from the manufacturer's tables rather than from photographs. On the employer side, OSHA 29 CFR 1910.134 requires a written respiratory protection program wherever respirators are required: hazard assessment, medical evaluation before use, annual fit testing on the exact make and model, training, and the cartridge change schedule described above. Voluntary users still get Appendix D information. Cartridge color coding is standardized too — magenta indicates P100 particulate, black organic vapor, white acid gas, and olive multi-gas — but colors are a cross-check, never a substitute for reading the approval label.

What pairs with respirator filters

Filters and cartridges are half of an assembly: they need an approved facepiece, and both need a fit test on that specific combination. Start with the filters and cartridges guide for the full decision tree, or the 3M Secure Click guide if you are on that platform — Secure Click uses a different attachment than the bayonet system and its filters are not interchangeable with 2000-series parts. Powered-air users should compare filters in our reviews of the 3M Adflo, RPB PX5, and Sundstrom SR 500.

Total cost of ownership

Cartridges are the recurring cost in any reusable respirator program, and the tempting economy — stretching them past the change schedule — is the one that eliminates the protection you are paying for. Two habits control real cost without touching the schedule. First, store unopened cartridges sealed and within their shelf life; an opened cartridge begins adsorbing ambient air whether or not you are wearing it, so bagging a partly used pair between shifts is standard practice, not an optimization. Second, use pre-filters where the manufacturer approves them: a cheap 5N11 pad in a 501 retainer catches the dust that would otherwise load an expensive combination cartridge, extending the life of the part underneath.

Respirator filters and cartridges FAQ

What is the difference between a filter and a cartridge?

Filters mechanically trap particulates — dust, fume, mists. Cartridges contain a sorbent bed that adsorbs gases and vapors. They protect against different hazard classes and are not interchangeable; combination units contain both.

What is the difference between P95 and P100?

Efficiency against the test aerosol. Both are oil-proof, but P95 filters at 95 percent and P100 at 99.97 percent. P100 is standard for lead, asbestos, and metal fume; the magenta color code identifies it.

Do I need the 501 retainer with these filters?

Only for pad-style pre-filters. The 3M 5N11 and 5P71 require the 501 retainer cap to hold them in place. The 2000-series filters — 2091, 2096, 2097, 2291 — attach directly to a compatible bayonet facepiece and need no retainer.

What do the nuisance acid gas and nuisance organic vapor labels mean?

They indicate a small amount of sorbent added to a particulate filter for relief from odors below the OSHA permissible exposure limit. Nuisance-level relief is a comfort feature, not respiratory protection against those gases — if the gas exposure is above the PEL, you need a proper cartridge.

Are these NIOSH approved, and what respirators do they fit?

Each product states its NIOSH approval and compatible facepieces on the manufacturer's listing. Approvals cover complete assemblies, so a filter is only approved with the facepieces its maker lists — check the compatibility table rather than assuming a physical fit means an approved one.

When should particulate filters be replaced?

When breathing resistance becomes noticeably higher, or when the filter is damaged, soiled, or contaminated. Unlike gas cartridges, particulate filters do not have a time-based change schedule; loading is the signal.

Can I tell a cartridge is spent by smelling the chemical?

No, and relying on it is dangerous. If you smell the contaminant you have already been exposed, and many chemicals have poor warning properties. Use an end-of-service-life indicator or a change schedule built from objective data, as OSHA 1910.134 requires.

Is there such a thing as a P200 filter?

No. NIOSH classes under 42 CFR Part 84 are N, R, or P combined with 95, 99, or 100 — there is no 200. P100 at 99.97 percent efficiency is the highest particulate class available.

Can I mix brands — a 3M filter on a Honeywell facepiece?

No. NIOSH approval applies to the complete assembly, so a cross-brand combination voids it even if the parts physically connect. Stay within one manufacturer's approved system.

What do the cartridge colors mean?

They are standardized hazard codes: magenta for P100 particulate, black for organic vapor, white for acid gas, olive for multi-gas and vapor. Treat color as a fast cross-check and read the approval label for the authoritative answer.

Do unopened cartridges expire?

Yes — cartridges carry a shelf life stated on the packaging, and sorbent performance degrades over time. Store them sealed in their original packaging, away from heat and contaminants, and check dates before issuing them.

Do I need a fit test if I only change the filter?

Fit testing is performed on the facepiece make, model, and size, so swapping to a different filter within the same approved system does not require retesting. Changing facepiece model or size does, and OSHA requires fit testing at least annually regardless.

Why trust WC Safety on respiratory protection?

WC Safety reviews workplace PPE full-time as an independent affiliate site — we do not sell products, hold no inventory, and accept no paid placements. In respiratory protection we hold the hardest line we apply anywhere: no breakthrough time, change schedule, or compatibility claim above is ours. Each traces to NIOSH 42 CFR Part 84, OSHA 29 CFR 1910.134, or the manufacturer's own approval and compatibility documentation, and every source is linked. Reviewed by Steven Eaton, WC Safety editor. Last reviewed: July 2026.