Règle correspondante
Canada
Practice Relating to Rule 10. Civilian Objects’ Loss of Protection from Attack
Section A. Civilian objects used for military purposes
Canada’s LOAC Manual (1999) states: “Where a civilian object is used for military purposes, it loses its protection as a civilian object and may become a legitimate target.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 4-5, § 37.
The manual further states: “Civilian vessels, aircraft, vehicles and buildings are military objectives if they contain combatants, military equipment or supplies.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 4-2, § 10.
Canada’s LOAC Manual (2001) states in its chapter on targeting:
407. Examples of objects which are military objectives
2. Civilian vessels, aircraft, vehicles and buildings are military objectives if they contain combatants, military equipment or supplies.
428. Civilian object used for military purposes
1. Where a civilian object is used for military purposes, it loses its protection as a civilian object and may become a legitimate target. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, §§ 407.2 and 428.1.