Standard Interpretations - Table of Contents
• Standard Number: 1910.144; 1910.145; 1910.145(d)

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

[February 22, 2011]

Richard A. Eichel, CSP
ATA Safety
1478 5th St. MS 7000
Arnold AFB, TN 37389

Dear Mr. Eichel:

Thank you for your November 29, 2010, letter to the Occupational Safety and Health Administration (OSHA), in which you ask whether OSHA will adopt and enforce the latest American National Standards Institute's (ANSI) standards regarding accident prevention signs and physical hazard marking. This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any question not delineated within your original correspondence.

Background: ANSI Z35.1-1968 (Specifications for Accident Prevention Signs) is incorporated by reference into 29 CFR 1910.6(e)(59). ANSI Z53.1-1967 (Safety Color Code for Marking Physical Hazards) is incorporated by reference into 29 CFR 1910.145(d)(2), (4), and (6). Both ANSI standards have become inactive and replaced by new standards (ANSI Z535.2 and ANSI Z535.1-6, respectively). The new ANSI standards, however, have not been adopted or incorporated by reference into an OSHA standard.