ASTM E84 Method for Determination of Surface Burning Properties of Building materials

 

Test principle

    The surface burning characteristics of the test material are compared with those of asbestos plywood and untreated red oak. Grade 0 is asbestos plywood and grade 100 is untreated red oak flooring material. The flame propagation rate of various untreated woods ranges from 60 to 230. In this test, the smoke produced during the combustion process is also measured and graded on the same scale. These grades are determined within the first 10 minutes. Unlike fire-resistant coatings, however, building codes require that the test time be extended from 10 minutes to 30 minutes, that the flame travel no further than 10 feet from the burner, and that there be no signs of further burning.

 

Test method

This method is used to determine the flame propagation rate of building materials (including solid plastics) (and to determine the smoke generation). According to ASTM E 84, the equipment used in the tunnel method is 7.62m long and the cross-sectional area of the opening end is 0.45m×. 0.30m steel trough lined with firebrick with window on the side. When measuring, the sample is placed under the top of the steel groove and supported by the inner wall of the groove to form a flat top in the groove.

 

When the flame propagation rate is measured by this method, the flame propagation rate is estimated according to the time of flame passing through the window after the sample is lit. The method is to plot the time of flame passing through the window by the distance of the window to obtain the flame propagation rate curve. During the test, the equipment is calibrated first, and then two preliminary tests are carried out first. The first preliminary test was to examine the red oak specimen, and its flame propagation and smoke generation (this method also determined the smoke generation of the material) were artificially assigned to 100. The second preliminary test is to detect the asbestos cement specimen and set its above two values to 0. Then, the smoke generation and flame propagation rate curves of the tested part are measured, and the flame propagation index (FSI) of the tested material is calculated, such as the total area AT&le under the curve of the tested material; 29.7 m· min, then FSI=0.515AT; Such as AT> 29.7 m· min,

 

Test requirements

Tall buildings and corridors, required FSI< 25,FSI=25-100 materials can only be used in places with low fire protection requirements, FSI> 100 material does not meet the flame retardant requirements. The standard divides FSI values into three categories: Class A 0-25, Class B 26-75, and Class C 76-200. At the same time, the smoke index is less than 450.

 

This method is equivalent to NFPA 5, UL 723, and is used to determine the FSI of general building materials for Class A from 0 to 25, Class B from 26 to 75, and Class C from 76 to 200, with a smoke index less than 450 (or smoke density not greater than 75 as determined by ASTM D 2843). For rigid foam, the FSI should be less than or equal to 25 (or 75 for ASTM D 2843 method) and the smoke index should be less than 450.

 

Similar methods are Canada CAN/ULC-S 102 tunnel method, and small tunnel furnace method China's industry standard has ZBG 5100-2-85(fire retardant paint fire performance test method), the United States standard has ASTM E 69-50 and so on.

 

Relevant standards

ASTM E136 Method for Determination of Material Properties under vertical Tube furnaces at 750C

 

ASTM E162 Determination of Surface Combustion Properties of Materials Using Radiant Heat Energy

 

ASEM E662 Standard test method for specific optical density of Smoke produced by solid materials

 

BS 476 Fire tests for building materials and structures

 

EN 13501-1 - Fire classification of building products and structures - Part 1: Classification using reaction to fire test data