Definition
Net explosive content is the mass of pyrotechnic composition contained in a firework, excluding casing, cardboard, clay and supports: it is what burns or explodes. It appears on the label and in the instructions of every product, in grams, and matches the net explosive mass used by the ADR. In France it is the trigger for the display declaration: CERFA 14098 is mandatory as soon as the display includes F4 or T2 articles, or as soon as the total net explosive content exceeds 35 kg, even with F2 and F3 products only. It also drives storage thresholds (ICPE nomenclature) and transport thresholds (ADR 1.1.3.6). Abroad, Spain uses the same NEC and grades its authorisations at 10, 50 and 100 kg.
In practice, for the display company
A display's total net explosive content changes with every edit of the firing plan, and it decides whether the CERFA is due. PyroDesk stores the NEC on each catalogue reference, totals the job in real time, writes it into the pre-filled CERFA and reuses it for stock and transport.