NIOSH ratings

The **NIOSH ratings** are a set of rules that NIOSH uses to check respirators. Today, the rules NIOSH uses is called **42 CFR 84**. NIOSH uses these rules to check N95 respirators. Before the N95, other rules have been used in the past, like 30 CFR 11. Also, some less-seen respirators can have filters that can be changed. These respirators are called elastomeric respirators. See the last chart for other less-seen respirators. NIOSH checks all these less-seen respirators too.

Under 42 CFR 84, rules for chemical filters are also made by the American National Standards Institute. One rule is called ANSI K13.1-1973, which are rules for chemical cartridge colors. To stay simple, ANSI's color rules are *not* listed below.

## Old ratings 
### Bureau of Mines 
The first respirator rating rules were made due to miners dying. By 1907, 3,243 miners had died. The United States Bureau of Mines (USBM) was made to give out information for miners and mine owners, so fewer miners would die. Some respirator rules were made, but few wanted rules that had to be followed.

Then, in 1929, the Hawks Nest Tunnel Disaster happened. The number of dead was so great from the breathing of silica (silicosis), that the USBM had to make respirator rules that people had to follow. The rules at the time checked respirators with dust that made people sick. Each dust rule is checked by itself before being passing the check. They were:
* Type A - **Dust**
* Type B - **Fume** - tested with lead fume
* Type C - **Mist**
Soon, "Type A/B/C" was seen less over time. People often said 'Dust/Fume/Mist' in place of 'Type A/B/C'. And often, respirators passed most of the 'Dust', 'Fume', and 'Mist' rules.

Some abbreviations of these respirators include: 'DM' and 'DFM', which are 'Dust/Mist' and 'Dust/Fume/Mist' ('Fume' is not in the chart above).

In 1973, the Los Alamos National Laboratory said NIOSH should use salt to check DM and DFM respurators. The amount of dust *not passed*, using salt, was really 75% to 90%. Using silica made the respirators look better than they actually were.

## Ratings today, under 42 CFR 84 
 in color.]]
 is also a Part 84 respirator.]]
In 1995, NIOSH made new respirator rules. The rules are stored in 42 CFR 84 in the Code of Federal Regulations (CFR). The CFR is part of the Federal Register. HEPA, or 'HE', is now only used for powered air-purifying respirators. In 2020, new ratings were added for these respirators. They were PAPR100-N and PAPR100-P. HEPA for other respirators is now 'P100'. P100 is the only type of filter or respirator that can have the color magenta. Also, the NIOSH approval label for 42 CFR 84 is not the same as the label for 30 CFR 11.

Under the new rules, MSHA stopped checking respirators.

Under 42 CFR 84, respirators should be tested with salt dust if the rating starts or ends with the letter 'N'. The amount of salt dust is 200 milligrams (mg). Dioctyl phthalate is used if the rating starts or ends with the letter 'R' or 'P'. 'R' and 'P' mean the respirator or 'filter' is made to stop oil mist. For 'R', the amount of DOP mist used is 200 mg. For 'P', the amount of DOP mist used does not have a number. It does not stop for a long time. All the new ratings are below:

If the rating ends in 100, the respirator or filter can stop asbestos.

## Last chart: Type of respirator by TC number 
This chart shows which less-seen respirator each TC number goes to. This can be used to check if a respirator is real in the NIOSH *CEL*.

N95s use the TC number 'TC-84A'.

## Other websites 
*NIOSH *CEL*
*NIOSH Pocket Guide to Chemical Hazards will tell you what respirator to use for bad chemicals.

## References
## Related pages
*Gas mask
*N95