Fire Rating

A number of requests have been made about the fire rating of SoftForm Lighting's fabric diffusers. The basis of that evaluation comes from the ASTM ( American Society for Testing and Materials) E84 test. The E84 is one of the most frequently specified standard test methods for assessing the surface burning characteristics of building products. The purpose of this test is to observe the flame spread along a sample in order to determine the relative burning behavior of the material.


There are three classifications within the 2015 International Building Code (IBC) that are addressed by the E84 test. Specially section 803.1.1 Interior wall and ceiling finish materials. This section details the following:

  • Class A: Flamespread Index 0-25; Smoke Developed Index 0-450

  • Class B: Flamespread Index 26-75; Smoke Developed Index 0-450

  • Class B: Flamespread Index 76-200; Smoke Developed Index 0-450

SoftForm Lighting fabric diffusers meet the Class A rating requirements with a Flamespread Index of 0 and a Smoke Developed Index of 250.


View and/or download the full ASTM E84 test results.

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