ICC-ES AC23

Full Name

ICC-ES AC23 – Acceptance Criteria for Sprayed Fire-resistant Materials (SFRMs), Intumescent Fire-resistant Coatings and Mastic Fire-resistant Coatings Used to Protect Structural Steel Members

Scope

ICC-ES AC23 outlines the requirements and test procedures for evaluating the performance of fire-resistant materials (FRMs) applied to structural steel members. The scope of AC23 includes:
  • Material evaluation: assessing the physical and chemical properties of FRMs, such as adhesion, density, and thickness.
  • Fire resistance testing: conducting standardized fire tests to determine the fire resistance rating of the FRM-protected steel assembly. This rating indicates how long the assembly can withstand fire exposure before failure.
  • Durability testing: evaluating the durability of FRMs under various environmental conditions, such as moisture, temperature fluctuations, and impact.
  • Quality control: establishing quality control measures for manufacturers to ensure consistent product quality and performance.
  • Installation requirements: providing guidelines for the proper application of FRMs to ensure optimal fire protection.
The FRMs covered under AC23 are:
  • Sprayed fire-resistive materials (SFRMs): these materials are applied by spraying onto the steel surface to form a protective layer that insulates the steel from heat during a fire.
  • Intumescent fire-resistive coatings: these coatings expand and char when exposed to high temperatures, creating a protective layer that insulates the steel.
  • Mastic fire-resistive coatings: these thick coatings are troweled onto the steel surface and provide insulation through a combination of thermal and chemical reactions.
By defining the requirements and test procedures for these FRMs, ICC-ES AC23 helps ensure that structural steel members are adequately protected from fire and can maintain their structural integrity during a fire event. This is essential for building safety and occupant protection.

Resources

Keywords

ICC-ES AC23; fire-resistive materials (FRMs); structural steel; sprayed fire-resistive materials (SFRMs); intumescent fire-resistive coatings; mastic fire-resistive coatings; adhesion; density; thickness; cohesion; air permeability; fire resistance rating; standard fire tests; temperature; flame spread; smoke developed; moisture resistance; temperature cycling; impact resistance; corrosion resistance; quality control; application methods; building codes; life safety