United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Question 452: The following questions refer to the

selection and use of a half-mask face piece, as described

in Appendix A, "Protection Factors for Respirators":


a. Footnote "g" of Appendix A states that "this type of

respirator is not satisfactory for use where it might be

possible (e.g., if an accident or emergency were to occur)

for ambient airborne concentrations to reach instantaneous

values greater than 10 times the pertinent values in table

1, column 3 of Appendix B...," i.e., the derived air

concentrations (DACs) for inhalation. Is this provision

intended to apply to the work activity in progress for

which the respirator is being used, or is it more broadly

applicable to the type of facility or licensed activity?

For example, is the statement intended to exclude the use

of a half-mask face piece respirator at a nuclear power

plant? We believe that the use of half-mask face piece

respirators should be permitted with the same limitations

as are applied to other respirator types because the use of

a half-mask face piece may offer advantages over, for

example, a full face piece respirator in some applications

by keeping the overall total effective dose equivalent

ALARA. This would appear to be in keeping with the intent

of §20.1703, Use of Individual Respiratory Protection

Equipment, which states that ". . . the licensee may select

respiratory protection equipment with a lower protection

factor only if such a selection would result in keeping the

total effective dose equivalent ALARA."



b. Footnote "g" requires that ". . . the mask is to be

tested for fit prior to use each time it is donned . . ."

for the use of half-mask face pieces. Is a negative

pressure test an acceptable method to adequately test the

respirator prior to use? Such a qualitative test method

would seem to be acceptable because it appears that there

would be no practical method to accomplish a quantitative

test in the field prior to each use.



Answer:



(a) This provision is intended to apply to situations in

which the ambient airborne concentrations are likely ". . .

to reach instantaneous values greater than 10 times the

pertinent values in table 1, column 3 of appendix B . . ."

The statement is not intended to exclude the use of a

half-mask face piece at a nuclear power plant or other

licensee facility.



(b) Yes. See NUREG-0041, Section 8.5.2.3, for four

acceptable testing methods for field testing of respirator

operation (isoamyl acetate, irritant smoke, negative

pressure test, and positive pressure test). (Reference: 10

CFR 20, Appendix A).









Page Last Reviewed/Updated Thursday, March 29, 2012