July 11, 1994
MEMORANDUM FOR: AREA DIRECTORS
ASSISTANT REGIONAL ADMINISTRATORS
FROM: JAMES P. DRAKE
Acting Assistant Regional Administrator
for Technical Support
SUBJECT: Respirators and Isocyanates
This memorandum replaces the February 15, 1991, memorandum (copy attached)
to Larry Falck, Acting Area Director, Jacksonville Area Office, concerning
1910.134 Interpretations, and clarifies the Agency's policy concerning
respirator use for spray operations involving paints containing isocyanates.
This action is necessary as the February 15, 1991, memorandum has been
inadvertently applied to operations other than spray operations.
Positive pressure air-line respirators are the only NIOSH-approved
respirators for employees engaged in spray operations and who are exposed to
isocyanates. A full-facepiece respirator is required because of the eye
irritant and sensitization characteristics of isocyanates. In situations
where an overexposure to isocyanates has not been established and an improper
type of respirator is being used a citation under 29 CFR 1910.134(b)(2) shall
be issued, provided that the compliance officer documents that an
overexposure is possible. Such documentation may be accomplished, for
example, either by documenting the existing work practices of the employee
during the spray operation or through air monitoring.
[OSHA Instruction CPL 2.103, dated August 26, 1994, Chapter III, paragraph
C.3.c. discusses guidance to the field where violations of the respirator
standard exist and Chapter III, paragraph C.3.a.(1)], discusses
violations of air contaminant standards.
Should you have any questions concerning this matter, please contact Sven
Rundman of my staff at (404)347-2281.