Respirator cartridges, and filters can protect dentists, and their employees from a variety of hazardous contaminants, but only if the respirator cartridges are properly matched to the hazards one is trying to obtain protection from.

Since it is the employer’s responsibility to provide policies, programs, training, and guidance on respirator use, do you know when to use respiratory protection? If so, do you understand what type of protection to choose and how to use it properly?

Read on to learn about the types of dental mercury exposures and how to properly protect employees.

Types of mercury dentists are exposed to.

A multitude of studies can be found in the scientific literature showing the process of removing amalgam dental fillings exposes the dentist and their employees to both mercury vapor (as released from the heating of elemental mercury during removal) and mercury contaminated particulate matter that can be less than one micron in size.

In the video below, Mark Richardson PhD (formerly of Health Canada) discusses his study, “Inhalation of mercury-contaminated particulate matter by dentists” published in the Journal of Human and Ecological Risk Assessment, which examined the amount of mercury contaminated particulate matter dentists are exposed to from the removal of amalgam fillings.

New scientific study on mercury particulate

In the video below, Dave Warwick, DDS, discusses his study “Mercury vapor volatilization from particulate generated from dental amalgam removal with a high-speed dental drill – a significant source of exposure” that was published in the peer-reviewed Journal of Occupational Medicine and Toxicology (JOMT) showing that the safety limits for mercury exposure (originating from previously unmeasured source of mercury particulate) can be exceeded during dental procedures involving the drilling on amalgam fillings. More information about this study can be found at the International Academy of Oral Medicine and Toxicology (IAOMT) website.

OSHA Respiratory Protection Protection Program

For dentists to properly protect themselves and their employees, they must utilize respirator cartridges that offer protection from both mercury vapor and mercury contaminated particulate matter. Employers should also be aware that OSHA requires employers to utilize only NIOSH approved respiratory protection. This is because NIOSH does extensive testing to verify that both the respirators and cartridges live up to the protection they claim. Also, if wearing respiratory protection, OSHA requires employers to implement a respiratory protection program as specified in OSHA’s Respiratory Protection standard 29 CFR 1910.134.

Manufacturers of Respirator Combination Cartridge for Mercury Protection

There are only three manufacturers in the United States that offer respirator cartridges which protect from both mercury vapors and the particles generated during amalgam removal.

3M Respirator cartridges

3M offers a combination cartridge (60927) to protect from both mercury vapor and particles. This combination cartridge is NIOSH approved only for use against mercury vapor, chlorine or sulfur dioxide and particulates.

The 3M combination cartridge (60927) below is for use with 3M™ Half and Full Facepieces 6000, 7000 and FF-400 Series with bayonet filter holders.

ImageNamePriceBuyShort Description
3M Mercury Vapor Cartridge/ P100 Mercury Particulate Filter 60927 (pair)
3M Mercury Vapor Cartridge/ P100 Mercury Particulate Filter 60927 (pair)$60.00 or subscribe and save up to 10%

Choose a REDUCED RATE subscription
None = Original price of $60

Quantity per package = 2. The 3M™ 60929s mercury vapor cartridge, P100 particulate filter combo is NIOSH approved and has been designed for use with 3M™ 6000, 6500, 7500 half mask series and the FF-400, 6000 and 7800 full face series of respirators. The 60929s protects against mercury vapor & particulates. The swept-back design allows an enhanced field of view and comfort. If you have not performed a Hazard Assessment to determine your filter change out schedule, 3M recommends changing the 60927 within 50 hours of exposure to mercury vapor, in accordance to your well-documented change-out schedule, or earlier if smell, taste, or irritation from contaminants is detected.

3M 6000 series full face respirator
3M™ 6000 Series Full Face Reusable Respirator Original price was: $200.00.Current price is: $180.00.

The 3M™ 6000 series full-facepiece reusable respirator features a soft, lightweight facepiece with easily adjustable 4 point head strap made from a silicone/thermoplastic elastomer for increased comfort.  The large, scratch-resistant polycarbonate lens ensures a wide field of view with excellent visibility and impact protection. This 3M Full Face Respirator is NIOSH approved for negative pressure air purifying and positive pressure dual airline applications. Replacement parts are available.

3M half facepiece reusable respirator 7502 medium
3M 7500 Series Half Facepiece Reusable Respirator$50.00

3M 7500 Series Half Facepiece Reusable Respirator uses advanced silicone material to help provide comfortable and durable respiratory protection. The 3M™ Cool Flow™ Valve helps make breathing easier and can reduces heat and moisture build-up for cool, dry comfort.

3m half facepiece reusable respirator 6200 medium
3M 6000 Series Half Facepiece Reusable Respirator$25.00

The 3M 6000 Series Half Facepiece Reusable Respirator is one of the lightest reusable half face piece respirators available that can protect against mercury. Its low-profile design provides exceptional visibility and accommodates safety glasses. The 3M™ 6000 Series Half Facepiece Reusable Respirator features easy-to-adjust head straps and a swept back design for the cartridges which improves balance and visibility.  For dentists removing mercury amalgam dental fillings, respirator should be used with NIOSH approved 3M™ Mercury Vapor Cartridge/ P100 Mercury Particulate Filter 60929S or combination cartridge / filter set.

ImageNamePriceBuyShort Description

In the past, some dentists unknowingly utilized 3M 6009s cartridges that only offered protection from mercury vapors. If you have this cartridge, please consider replacing with the 60927 cartridge listed above.

MSA Adavantage and Comfo Classic Series

Safety company MSA manufacturers two different combination cartridges that fit two different respirator series that dental professionals can use for protection against mercury.

The streamlined Advantage® Mersorb P100 combination cartridge (815368) protects from both mercury vapors and particles. This is the smallest of all the mercury cartridges and when paired with one of the respirators below, it fits comfortably underneath our visor face shield.

ImageNamePriceBuyShort Description
MSA Advantage mercury filter 815368 pair
MSA Mersorb P100 Advantage® Respirator Cartridge 815368 (pair)$65.00 or subscribe and save up to 10%

Choose a REDUCED RATE subscription
One Time = Original price of $65

The MSA Mersorb P100 Advantage® Respirator Cartridge is compatible with Advantage® series air purifying respirator is designed to give protection against chlorine and mercury vapors. When used with a P100 prefilter it offers extra protection against all particulates.  Provide lightweight, low-profile performance. Cartridges fit Advantage® 200 LS and 420 half-masks, and 1000, 3000, and 4000 series full-facepiece respirators. This respirator cartridge is rendered with a bayonet-style design for quick mounting which locks into place with one twist.

ImageNamePriceBuyShort Description

The Advantage® Mersorb P100 combination cartridge also fits across multiple series of MSA’s reusable half and full mask respirators found below.

ImageNamePriceBuyShort Description
MSA Advantage 200 LS Half Mask Respirator
MSA Advantage 200 LS Half-Mask Respirator$40.00

The MSA Advantage 200 LS Half-Mask Respirator is a comfortable, efficient and economic half mask. With its patented MultiFlex system the Advantage 200 LS offers maximum protection and high wearing comfort. The soft, pliable combination of rubber and plastic provides a customized and pressure-free fit, instantly conforming to the wearer’s unique facial characteristics. The Advantage 200 LS comes in three sizes.

MSA Comfo Classic
Additionally, MSA also produces a combination cartridge called the Comfo Mersorb P100. They are sold as a pair of three in a box and they fit the Comfo Classic® Half-Mask Respirator series.

ImageNamePriceBuyShort Description
MSA Mersorb P100 NIOSH Respirator Filter Cartridges Box 815185
MSA 815185 Comfo Combination Cartridge, Mercury Vapor and P100 Filter (Box of 3 pair)$265.00 or subscribe and save up to 5%

Choose a REDUCED RATE subscription
One Time = $265

This MSA Comfo 815185 Metallic Mercury Vapor and Chlorine cartridge with P100 particulate filter is designed to provide great protection and is fully approved by NIOSH. The P100 filter is 99.97% efficient against all particulate aerosols. The Comfo 815185 cartridge has a threaded connection type and is built to fit the MSA Ultra and Comfo respirator series. These cartridges are sold in box of 3 pair.

MSA Classic Comfo SILVER Respirator Harness
MSA Comfo Classic® Half-Mask Respirator$55.00

The MSA Comfo Classic® half mask respirator is NIOSH approved and the Softfeel™ Hycar rubber facepiece provides exceptional comfort for extended wear. Users are ensured a contoured fit on any face with MSA Comfo Classic® halfmask respirators using this unique face seal design.

ImageNamePriceBuyShort Description

Honeywell North

We currently do not offer respirators and cartriddges from Honeywell North. But we are working to secure a supply chain of their 5500 and 7700 series half mask respirators as well as their combination cartridges for both mercury vapor and particulate protection.


When looking at the ratings on filters and pre-filters you will see N95 or P100 listed. The number in a rating tells you the minimum amount of airborne challenge particles the mask protects against: an N95 mask keeps out at least 95% of particles but is not oil resistant, and a P100 mask is oil proof while protecting the wearer from at least 99.8% of particles.

Respirator Rating Letter Class

N – Not oil resistant
R – Resistant to oil
P – Oil Proof

Respirator Rating Number Class

95 – Removes 95% of all particles that are at least 0.3 microns in diameter
99 – Removes 99% of particles that are at least 0.3 microns in diameter
100 – Removes 99.97% of all particles that are 0.3 microns in diameter or larger. HE or HEPA quality filter.


Since users have been known to overlook the instructions that come with the respirator cartridges, we want to highlight a few critical points that emphasize the importance of matching the proper cartridge and filter against the correct hazard contaminant.

Cartridge / Filter Use Instructions

1. Failure to follow all instructions and limitations on the use of these cartridge/filters and/or failure to wear the respirator during all times of exposure can reduce respirator effectiveness and may result in sickness or death.

2. Before occupational use of these cartridge/filters, a written respiratory protection program must be implemented meeting all the local applicable requirements. In the U.S., follow OSHA 29 CFR 1910.134 which includes medical evaluation, training and fit testing. In the U.S. users must also comply with applicable OSHA substance specific standards. In Canada, CSA standard Z94.4 requirements must be met and/or requirements of the applicable jurisdiction, as appropriate. In Brazil, follow the requirements of the Respiratory Protection program of the Ministry of Labor.

If you have any questions, please leave them for us in the comments below.