A quarter-scale room fire test developed at NBS was used to help develop a preliminary approach for fire hazard assessment of wall-ceiling combinations of hull insulation materials.The quarter-scale test has been refined to include measurement of heat release rate, smoke, and carbon monoxide.In addition, polyphosphazene foam insulations were evaluated with this test The quarter-scale test was also modified for testing mattress insert materials, including polyphosphazene foam. Existing tests, used for measuring total heat, rate of heat release, and smoke production, were also used to evaluate these materials. Heat release rate measurements with the Ohio State University apparatus and smoke measurements with the ASTM E 662 test, modified for horizontal placement of specimens, gave adequate evaluation of the fire hazards of mattress insert materials.