This document specifies a small-scale laboratory screening procedure for comparing the relative burning characteristics of horizontally oriented, small cellular plastic specimens having a density less than 250 kg⋅m−3 determined in accordance with ISO 845, when exposed to a small-flame ignition source. NOTE Another International Standard which covers flexible cellular plastic and cellular rubber is ISO 3582[2]. This method of test is intended for quality assurance and limited product evaluation of cellular plastic materials under controlled laboratory conditions, and is not intended to assess the fire behaviour of, for example, building materials or furnishings under actual fire conditions. The optional classification system described in Annex A is intended for the pre-selection of cellular plastic materials for products, including the determination of the ranges of material parameters that give the same classification (see 6.1).