United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Respirator User's Notice - Use of Unapproved Subassemblies

HPPOS-147 PDR-9111220069

Title: Respirator User's Notice - Use of Unapproved


See the above entitled notice issued by J. B. Moran on

November 6, 1984. This notice states that NIOSH / MSHA

approves only complete respirator assemblies and not

subassemblies such as cylinders or air supply hoses. Users

of approved respirators must not interchange subassemblies

or make unapproved modifications to respiratory protection


The National Institute for Occupational Safety and Health

(NIOSH) had received many questions and complaints in

regard to the interchangeability of respirator

subassemblies and unapproved modifications to NIOSH / MSHA

certified respirators. Further, some problems reported to

NIOSH had, upon investigation, been found to have been

caused by user's modifying certified respirators that

resulted in the modified respirator failing to perform as

anticipated, thus jeopardizing the respirator user.

NIOSH / MSHA respirator certification regulations, Title 30

Code of Federal Regulations Part 11 (30 CFR 11), state that

approved respirators "are maintained in an approved

condition and are the same in all respects as those

respirators for which a certificate has been issued." [30

CFR 11, 11.2 (b)] In addition, the regulations permit

NIOSH / MSHA to approve only complete respirator assemblies

and prohibit the approval of respirator subassemblies such

as cylinders or air supply hoses. These requirements are

intended to ensure that one manufacturer has overall

control and responsibility for the integrity of the

approved respirator.

In some cases even minor modifications to respirators may

make significant changes in the performance of the

respirator. Manufacturers who modify certified respirators

must test the modification to determine if the respirator

continues to meet the minimum requirements of 30 CFR 11,

and must submit the modifications to NIOSH. A user who

modifies a certified respirator may not be able to

determine whether a change will decrease respiratory

protection. Several cases have been reported to NIOSH

where unapproved modifications or use of an unapproved

subassembly have resulted in respirator failures.

Therefore, users of NIOSH / MSHA approved respirators are

cautioned against interchanging subassemblies or making

unapproved modifications to their respiratory protective


Regulatory references: 10 CFR 20.103, 10 CFR 20.1703

Subject codes: 8.10

Applicability: All

Page Last Reviewed/Updated Thursday, March 29, 2012