Test for the determination of glass fibre content

The glass fibre content of glass fibre grids is determined by the calcination method: small specimens of 2 to 20 g are placed in muffle furnace set at 625 °C, leaving only the glass fibre as a residue after heating. A glass fibre content is calculated from the masses of each specimen before and after calcination. The whole procedure is performed according to standard NBN EN ISO 1172, method A.