3M 6391 Half Facepiece Respirator Assembly Kit with P100 Filters, Large

The 3M 3M 6391 Half Facepiece Respirator Assembly Kit with P100 Filters, Large is respiratory protection listed on Amazon by 3M. This page summarises the published specification and explains how it fits the NIOSH approval and OSHA program requirements that govern everything in our respiratory protection range.

Key details from the 3M listing

• 3M 6391 Half Facepiece Respirator Assembly Kit with P100 Filters
• Large

Where half mask respirators fit in your PPE program

A respirator only protects when it is the right class for the contaminant, sealed to a clean-shaven face, and backed by a written program. That program covers hazard assessment, medical evaluation, fit testing, training, cartridge change schedules, and maintenance. Compare our full-face respirators, disposable respirators, and respirator filters and cartridges to match class to hazard.

What the standard requires

NIOSH approves respirators under 42 CFR 84 as complete assemblies, and OSHA 1910.134 governs how they are used at work: medical evaluation, annual fit testing, and a documented change schedule. Assigned protection factors are 10 for half-mask and 50 for full-facepiece air-purifying respirators. See N95 respirators and P100 respirators.

How to choose the right one

Identify the contaminant first: particulates need an N, R, or P filter, while gases and vapours need the matching chemical cartridge. Then choose half-mask or full-face depending on whether the eyes also need protection, and size the facepiece so a fit test passes. Compare PAPR filters, PAPR cartridges, and 3M half-mask respirators.

Care, inspection and replacement

Disassemble and wash reusable facepieces with a mild cleaner, air-dry away from sunlight, and store sealed away from contaminants. Inspect straps, valves, and the sealing surface before each use, and replace cartridges on schedule. See 3M full-face respirators and Moldex disposables.

Who this suits - and who should look elsewhere

This suits workers with a known, measured contaminant and an employer-run respiratory program behind them - hazard assessment, medical clearance, fit testing, and a cartridge change schedule. It is not suitable for unknown atmospheres, oxygen-deficient or IDLH spaces, or anyone who cannot maintain a clean-shaven seal. In those cases you need supplied air or an SCBA, and confined-space work needs atmospheric testing with surgical N95 respirators first. Compare head and eye protection when eye protection is also required.

How we assess this product

WC Safety is an independent PPE review and research site. We do not sell, ship, or stock anything, and we have not physically tested this half mask respirator. What we do is read the published 3M specification against the governing standard, flag what the listing does and does not state, and place the product in context next to the alternatives we cover. Where a number matters for compliance - a rating, a class, a temperature, a voltage - we take it from the manufacturer listing and expect you to confirm it on the live listing before you buy. The star rating on this page belongs to Amazon customers, not to us. Read more across our gas detectors and safety glasses coverage.

Related gear to compare

surgical N95 respirators · head and eye protection · gas detectors · safety glasses · safety goggles · workplace PPE · hand protection · hard hats

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