An official website of the United States government

Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Coffee break Bulletin

Inspecting fire-resistive steel construction for damage

Steel is used in heavy construction because it is relatively inexpensive, easy to use and provides great strength under normal conditions. However, heat is its weakness. Exposed steel expands and may fail under fire conditions.

Physical damage can cause the concrete to separate from the steel compromising the structure's fire-resistive integrity. Exposed steel can fail when its average temperature reaches approximately 1,000 F. The high temperature will weaken the steel resulting in sagging that might result in catastrophic structural failure.

According to the National Fire Protection Association (NFPA) and the International Code Council (ICC), steel structural elements must be protected to a minimum one-hour fire-resistance rating. The steel's fire-resistance rating is achieved through a concrete, or intumescent (swells when heated) paint, coating. The current term for spray fireproofing is “spray-applied fire resistive material.”

The most common fire-proofing materials are low-density fiber or cement coatings that are sprayed directly onto the steel. These require the oily coating found on new steel to be removed prior to spray application or the material will not stick. However, a thin film of rust will help adhere these materials to bare metal.

Fire code requirements

Fire inspectors should be familiar with the many elements that make up fire-resistive construction, and if they see damaged components, they should order corrective action.

The model fire codes authorize the fire inspector to require repairs to damaged fire-resistive assemblies. For additional information, refer to NFPA 1, Fire Code, Chapter 12; International Building Code, Chapter 7; and International Fire Code, Chapter 7.

National Fire Academy training opportunities

Explore more Coffee Break Bulletins:

  • Filter:
community members meeting about wildfire projects
temporary standpipe
firefighters on hose line
binary data with a question mark
fire sprinkler system
table made up of puzzle pieces
helicopter dropping water on a fire