How to Select a Respirator

Before you select a respirator, there are some general questions you will need to answer. See the tabs below for important questions you need to ask yourself before choosing a respirator
Additional Resources:
Putting on (Donning) Your Respirator
Types of Respirators and Cartridges
Fit Checking Your Respirator
How to Fit Test Your Respirator
Are you using pesticides?

If YES, look on the pesticide warning label to see what respiratory protection is required. (For more information see the "How do I know what type of a respirator to use for spraying pesticides").

If NO (you are using another type of chemical), call your local safety supplier for a suggestion on the type of respirator you should be using.

Does the substance irritate your skin or eyes?

If YES, you may choose to wear a full-face respirator.

If NO, you can use a half-mask respirator.
Is the hazard Immediately Dangerous to Life and Health (IDLH), or is there a lack of oxygen?

(In IDLH atmospheres the concentrations are high enough or the substance is dangerous enough that exposure could kill you.)

If YES, you should avoid entering the area whenever possible. If you must enter, you will need a respirator that supplies breathable air, such as a self-contained breathing apparatus (SCBA) unit, which consists of a portable tank of air; or a supplied air system (with an emergency escape bottle), which supplies air via a pump or an air compressor. (You should also monitor the air to determine the level of contaminants present.)

What is the difference between a particulate filter and a chemical cartridge?

Particulate respirators, filters and pre-filters - trap solid and liquid particles such as dusts, mists and fumes. They can be found in the form of a disposable respirator, or in the form of a "pre-filter", which can be used in conjunction with a chemical cartridge. The filters should be changed according to the manufacturer's instructions or when you experience excessive breathing resistance.

Chemical cartridges - (Gas and/or Vapor-removing Cartridge-type Respirators) are filled with specially treated activated carbon which will adsorb certain gases and/or vapors. You should change the cartridges when you taste or smell a substance, or your eyes, throat or respiratory system become irritated. It's best to schedule a cartridge "change-out" before you notice that you are being exposed to the contaminant.

Chemical Cartridge Color Coding
All manufacturers use the same color coding for gas/vapor protection
Acid Gas
Organic Vapors
Ammonia Gas
Acid Gas & Organic Vapor
Mulit-gas (protects against numerous gases and vapors)
Particulate Filter Cartridge (HEPA) (Also called P100)
(A HEPA is a particulate filter; all others are used for gases and/or vapors.)
What are pre-filters and when should you use them?

Pre-filters are used with cartridges. While the cartridges adsorb the gas or vapor, the pre-filters trap the dust and mist particulates. Pre-filters work well for activities like pesticide and paint spraying because they trap the liquid particles.
How do I choose a particulate (dust/mist/fume) respirator, filter or pre-filter?

To choose the appropriate respirator, you will need to review the following 4 questions.


A) Which respirator do I choose if I'm working around dusts, mists, fumes or agricultural molds?
You can wear an N95 in almost any dust situation. Exceptions: If you are welding a highly toxic metal that requires a HEPA (high efficiency) respirator, you should wear an N100 or a P100. Examples of highly toxic metals are lead and cadmium. OSHA also has certain substances that it has always required a HEPA respirator for, such as asbestos and lead.

B) What does 95 and 100 refer to in the N95 and P100 designations for particulate respirators? The numbers refer to the efficiency of the filter. The 95% filters are used for most applications and the nearly 100% efficient filters are used in place of the old HEPA filters for the more toxic particulate situations.

C) Are you spraying a pesticide or chemical?
If YES, you will need to choose a pre-filter.
Is the pesticide or chemical oil-based?

If NO, you can use a non-oil pre-filter, such as N95.

If YES, you must use an "Oil Proof or Oil Resistant" pre-filter, such as a P100. The R , P and HE filters can be used for aerosolized oil-based chemicals and pesticides. R means "Resistant to Oil" and P stands for "Oil Proof." The R filters last up to eight hours when used with oil; the P filters may last longer - follow the manufacturer's recommendations. N filters are "Not Resistant" to oil. If your chemical or pesticide does not contain oil, you may use an N, R, P  or HE filter.

Note: If you are unsure which particulate filter to choose, the P100 offers the highest level of protection against both oils and non-oils.

N =
Not to be used with oil.
R =
R means "resistant to oils." Can be used for eight hours with chemicals and pesticides that contain oil.
P =
P means "oil proof." Can be used with oil and non-oil hazards; may be able to use longer than eight hours.
HE =
High Efficiency, the filter used on a PAPR (Can be used with oils.) Check with manufacturer's instructions for time restrictions; or change when you notice a decrease in airflow.

D) Which particulate filter do I use if I am using a Powered Air-Purifying Respirator (PAPR), such as
You will use an HE, or high efficiency filter. The PAPRs use a HEPA filter for particulates, while the half-mask and full-face respirators use the N, R, P filters - i.e.. N95, P100.

How do I know what type of respirator to use for spraying pesticides?

Check your label.  OLDER LABELS will list a MSHA/NIOSH TC# (Ex: TC-23C), which refers to the respirator's approval number. NEW LABELS will list a respirator with a NIOSH TC approval # and describe the new NIOSH-approved respirator. For example, it may say: "NIOSH-approved respirator (Ex:TC-23C) with a pre-filter approved for pesticides; or a NIOSH-approved respirator with an organic vapor (OV) cartridge with any N, R, P, HE filter."

A sample label is provided below:


*An HE (high efficiency) filter is used with a PAPR (Powered Air-Purifying Respirator). Check with manufacturer's instructions for time restrictions when used with oil-based pesticides/chemicals that are sprayed. If there are no restrictions, replace the filter when you notice a decrease in the airflow.