Back to Federal guidance

Class C and Class B hard hats on construction sites

Summary A construction manager asked whether Class C hard hats were acceptable on heavy construction projects. OSHA said Class C helmets meeting the cited standard protected against falling and flying objects but offered no electrical protection. Workers exposed to high-voltage shock and burns needed compliant Class B helmets.
Document
Federal opinion letter
Agency
Occupational Safety and Health Administration (OSHA)
Document number
1979-12-17
Date issued
December 17, 1979
Status
Active
Status last verified October 10, 2026

Apply this to your situation

This page explains the general guidance. Ask about your specific situation and see what current federal labor law says, with citations.

About this page: The full text below is the official document from Occupational Safety and Health Administration (OSHA). Ezel adds the plain-English summary and tracks the document's status. The official source linked on this page is authoritative for any reliance.

December 17, 1979

Mr. J. F. Barrett
Resident Manager
Stone & Webster Engineering Corporation
[Recipient address omitted]
Dear Mr. Barrett

This is in response to your inquiry requesting clarification of the acceptance and use of a class C hard hat on heavy construction projects.

29 CFR 1926.100(b) requires that helmets for the protection of employees against impact and penetration of falling and flying objects meet the specifications contained in American National Standards Institute, Z89.1-1969, Safety Requirements for Industrial Head Protection. A class C helmet complying with ANSI Z89.1-1969 specifications is acceptable on construction projects for protection against impact and penetration of falling and flying objects. Class C provides no protection for electrical hazards.

29 CFR 1926.100(c) requires that helmets for the head protection of employees exposed to high voltage electrical shock and burns meet the specifications contained in American National Standards Institute, Z89.2-1871. A class B helmet complying with ANSI Z89.2-1971 specifications is required on construction projects for protection against high voltage electrical shock and burns. Normally, class B helmets provide the optimum protection for electrical workers and other crafts exposed to head hazards, electrical and nonelectrical.

If we may be of any further assistance, please feel free to call or write.

What does federal law require in your situation?

Ezel checks current federal labor law against your facts and answers with citations.

Opens in Ezel Pro.

  • Checks the law as it stands today, not only this page
  • Cites every source it relies on, so you can verify it
  • Chat, drafting and research in one workspace