This standard specifies the test method for determining the combustion performance of foam plastics using the horizontal burning method. It is applicable to the evaluation of the combustion performance of small, low-density foam plastic specimens under the influence of a small flame under laboratory conditions. The standard is not intended as a basis for assessing the fire hazard under actual use conditions. The test is typically conducted in a horizontal burning test chamber equipped with a Bunsen burner, specimen holder, scale, and timer. The method involves applying a standard flame to a horizontally clamped specimen and evaluating the material's combustion characteristics by observing and recording its burning behavior, such as whether the flame extinguishes or the rate of flame spread.