Соответствующая норма
Canada
Practice Relating to Rule 15. The Principle of Precautions in Attack
Section B. Avoidance or minimization of incidental damage
Canada’s Code of Conduct (2001) requires that the operations of Canadian forces be “conducted in such a way that damage to civilians and their property is minimized”. 
Canada, Code of Conduct for CF Personnel, Office of the Judge Advocate General, 4 June 2001, Rule 2, § 4.
Canada’s LOAC Manual (2001) states in its chapter on air warfare: “All reasonable precautions should be taken during the conduct of military operations in the air to avoid losses of civilian lives and damage to civilian objects.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 711.3.
Rule 2 of Canada’s Code of Conduct (2005) instructs Canadian Forces (CF) personnel: “In accomplishing your mission, use only the necessary force that causes the least amount of collateral civilian damage”. 
Canada, Code of Conduct for CF Personnel, Office of the Judge Advocate General, 2005, Rule 2.
The Code of Conduct further explains:
Whenever military force is used, civilians who are not directly involved in the conflict may be hurt and their property may be damaged. Indeed, the inaccuracy of weapons systems, the deployment of opposing forces in civilian areas and the general “fog of war” increases the likelihood of injury being unintentionally inflicted on civilians. CF operations must be conducted in such a way that damage to civilians and their property is minimized. 
Canada, Code of Conduct for CF Personnel, Office of the Judge Advocate General, 2005, Rule 2, § 4.