Page:DHHS Pub 96-101 NIOSH Guide to the Selection & Use of Particulate Respirators Certified Under 42 CFR 84.pdf/12

 

 

1. The selection of N-, R-, and P-series filters depends on the presence or absence of oil particles, as follows:

• If no oil particles are present in the work environment, use a filter of any series (i.e., N-, R-, or P-series).

• If oil particles (e.g., lubricants, cutting fluids, glycerine, etc.) are present, use an R- or P-series filter. Note: N-series filters cannot be used if oil particles are present.

• If oil particles are present and the filter is to be used for more than one work shift, use only a P-series filter.

 

Note: To help you remember the filter series, use
the following guide:

 

N for Not resistant to oil
R for Resistant to oil
P for oil Proof

 

2. Selection of filter efficiency (i.e., 95%, 99%, or 99.97%) depends on how much filter leakage can be accepted. Higher filter efficiency means lower filter leakage.

3. The choice of facepiece depends on the level of protection needed—that is, the assigned protection factor (APF) needed.