A technician crushed the elements composing a pyrotechnic ignition powder using a mortar and pestle apparatus; he was protected by a polycarbonate screen, a lab coat (with sleeves lowered) and leather gloves. The friction of pestle on mortar caused combustion of the 4 g of composition, made from lead oxide, silicon and collodion cotton.

The onset of fire, which arose under normal operating conditions, was of no consequence for personnel safety. The protective screen was slightly blackened. Another identical incident occurred on 25th November, 1988.