Соответствующая норма
Spain
Practice Relating to Rule 18. Assessment of the Effects of Attacks
Spain’s LOAC Manual (1996) states:
It shall not be decided to launch an attack when, from the information available at the time of the decision, it may be expected to cause damage to civilian persons and/or objects which would be excessive in relation to the concrete and direct military advantage anticipated from the attack as a whole and not only from isolated parts thereof. 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Publicación OR7-004, 2 Tomos, aprobado por el Estado Mayor del Ejército, División de Operaciones, 18 March 1996, Vol. I, § 2.5.b.
Spain’s LOAC Manual (2007) states:
The decision to launch an attack must not be implemented when, based on information available at the time the decision is taken, it could be expected to lead to casualties among the civilian population or cause damage to civilian property which would be excessive in relation to the military advantage anticipated from the attack considered as a whole and not only from isolated or specific parts of the attack. 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Tomo 1, Publicación OR7–004, (Edición Segunda), Mando de Adiestramiento y Doctrina, Dirección de Doctrina, Orgánica y Materiales, 2 November 2007, § 2.5.b.