Соответствующая норма
Practice Relating to Rule 85. The Use of Incendiary Weapons against Combatants
In 2005, in reply to a question concerning the use of chemical weapons in Iraq, the Italian Under-Secretary of State for Defence stated:
[T]he operational procedures regarding the employment of man-portable and detachment arms envisage the possibility to space out some tracer cartridges, which have on the bottom of the bullet the quantity of phosphorus needed to show a trace in order to verify the shots’ destination and to proceed to the adjustment of the selective fire, which is necessary to prevent the undesired effects of the fire. Such employment is absolutely consistent with international law provisions. 
Italy, Chamber of Deputies, Statement by the Under-Secretary of State for Defence, 1 December 2005, published in Italian Yearbook of International Law, vol. XV, 2005, pp. 381–382.