Abstract: A method of charging or recharging one or more agent storage containers which may be located at suitable locations about a high value room or area which is to be protected from fire or explosions. Some of the agent storage containers may be placed in relatively inaccessible locations and one or more can be discharged in response to the detection of combustion to immediately suppress or extinguish the fire or deflagration-type rapid combustion. Each type of container must be properly charged with a relatively precise predetermined mass of fire extinguishing fluid agent, such as bromotrifluoromethane or the like, for effective operation. The method of the present invention eliminates or greatly reduces the time, expense and safety hazards involved in prior charging methods by no longer requiring that the agent storage container be removed from its location and placed on a scale during the charging operation.