Соответствующая норма
Belgium
Practice Relating to Rule 85. The Use of Incendiary Weapons against Combatants
Section B. The use of incendiary weapons against combatants in particular
Belgium’s Law of War Manual (1983) states: “The use of [incendiary] weapons against persons is prohibited because they cause unnecessary suffering, but their use against military objectives, such as bunkers, tanks, depots, etc. is permitted.” 
Belgium, Droit Pénal et Disciplinaire Militaire et Droit de la Guerre, Deuxième Partie, Droit de la Guerre, Ecole Royale Militaire, par J. Maes, Chargé de cours, Avocat-général près la Cour Militaire, D/1983/1187/029, 1983, p. 38.