8-hour total weight average (TWA) permissible exposure limit (PEL).

OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

October 6, 1995

Mr. Mark Nicas
University of California
Environmental Health Sciences
School of Public Health
140 Warren Hall
Berkeley, California 94720-7360

Dear Mr. Nicas:

This is in response to your letter of July 7, addressed to Mr. Joseph A. Dear, Assistant Secretary for the Occupational Safety and Health Administration (OSHA), requesting an interpretation on 8-hour total weight average (TWA) permissible exposure limit (PEL) as defined in 29 CFR 1910.1000 and in other substance-specific health standards.

OSHA policy on using wipe sampling for 4,4' methylenedianiline (MDA) as the basis for enforcement action.

OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

July 18, 2003

Dee Woodhull, CIH, CSP
Organization Resources Counselors, Inc.
1910 Sunderland Place, N.W.
Washington, DC 20036-1608

Dear Ms. Woodhull:

Methylenedianiline (MDA) Standard for General Industry (29 CFR 1910.1050); Extension of the Office of Management of Budget's (OMB) Approval of Information-Collection (Paperwork) Requirements.

  • Publication Date:
  • Publication Type:
  • Fed Register #:
    65:11085-11086
  • Title:

DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. ICR-1218-0184(2000)]

Methylenedianiline (MDA) Standard for General Industry (29 CFR 1910.1050); Extension of the Office of Management of Budget's (OMB) Approval of Information-Collection (Paperwork) Requirements

AGENCY: Occupational Safety and Health Administration (OSHA); Labor.

ACTION: Notice of an opportunity for public comment.

4,4'-Methylenedianiline Standard for General Industry (29 CFR 1910.1050); Extension of the Office of Management and Budget's (OMB) Approval for Information-Collection (Paperwork) Requirements

  • Publication Date:
  • Publication Type:
  • Fed Register #:
    66:63071-63072
  • Title:

DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. ICR-1218-0184(2002)]

4,4'-Methylenedianiline Standard for General Industry (29 CFR 1910.1050); Extension of the Office of Management and Budget's (OMB) Approval for Information-Collection (Paperwork) Requirements

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Request for comment.

4,4'-Methylenedianiline (MDA) General Industry Standard (29 CFR 1910.1050); Extension of the Office of Management and Budget's (OMB) Approval of Information-Collection (Paperwork) Requirements

  • Publication Date:
  • Publication Type:
  • Fed Register #:
    68:41401-41403
  • Title:

DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. ICR-1218-0184(2003)]

4,4’-Methylenedianiline (MDA) General Industry Standard (29 CFR 1910.1050); Extension of the Office of Management and Budget's (OMB) Approval of Information-Collection (Paperwork) Requirements

AGENCY: Occupational Safety and Health Administration (OSHA); Labor.

ACTION: Request for comment.

Agency Information Collection Activities; Announcement of Office of Management and Budget (OMB) control Numbers Under the Paperwork Reduction Act

  • Publication Date:
  • Publication Type:
  • Fed Register #:
    69:5587
  • Title:
DEPARTMENT OF LABOR

Occupational Safety and Health Administration

Agency Information Collection Activities; Announcement of Office of Management and Budget (OMB) control Numbers Under the Paperwork Reduction Act

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Notice, Announcement of OMB approval of information collection requirements.
SUMMARY: The Occupational Safety and Health Administration (OSHA) announces that the Office of