According to GB/T 5169.10-2017/IEC 60695-2-10:2013

4.4 The prescribed bottom layer

To assess the potential spread of combustion (such as combustion caused by falling particles or burning particles from the specimen), a designated bottom layer is placed under the specimen.

Unless otherwise specified, wrap a layer of packaging paper tightly on the upper surface of a wooden board (smooth and with a minimum thickness of 10mm), and place it 200mm ± 5mm below the point where the hot wire is applied to the sample.

Silk paper (according to ISO 4046-4:2002 4.215) is a soft and strong lightweight packaging paper with a unit area mass of 12 g/m2~30 g/m.

5.2 Calibration of Temperature Measurement System:

The temperature measurement system specified in 4.3 shall be periodically calibrated using the following program:

A silver foil with a purity of at least 99.8%, an area of about 2mm ², and a thickness of about 0.06mm can be placed on the upper surface of the top of the hot wire to complete the single point verification of the hot wire temperature. The starting temperature of the hot wire should be set slightly below the melting point of the silver foil and stabilized. Then heat the hot wire at a low heating rate to accurately observe the melting point. When the silver foil begins to melt, the thermometer should display

960 ° C ± 10 ° C. After confirming the completion of the program, all silver residues on the hot wire should be immediately removed while it is still hot to reduce the possibility of it melting into an alloy.