Some manufacturers recommend shaking your dry chemical extinguishers once a month to prevent the powder from settling/packing.
Fire extinguishers should be pressure tested (a process called hydrostatic testing) after a number of years to ensure that the cylinder is safe to use. Consult your owner's manual, extinguisher label or the manufacturer to see when yours may need such testing.
If the extinguisher is damaged or needs recharging, replace it immediately!
An inspection is a “quick check” to give reasonable assurance that a fire extinguisher is available, fully charged and operable. The value of an inspection lies in the frequency, regularity, and thoroughness with which it is conducted. The frequency will vary from hourly to monthly, based on the needs of the situation. Inspections should always be conducted when extinguishers are initially placed in service and thereafter at approximately 30-day intervals.
Fire extinguishers should be maintained at regular intervals (at least once a year), or when specifically indicated by an inspection. Maintenance is a “thorough check” of the extinguisher. It is intended to give maximum assurance that an extinguisher will operate effectively and safely. It includes a thorough examination and any necessary repair, recharging or replacement. It will normally reveal the need for hydrostatic testing of an extinguisher.
To ensure that the fire extinguisher works in the event of a fire, you should follow these guidelines:
The resulting consequences of negligent, or lack of, fire extinguisher maintenance could be grave. In order to avoid problems that could arise at the moment when someone is in desperate need of a fire extinguisher, maintenance should be carried out at least once a month. The disaster of a small fire in a home, restaurant, or office building can be avoided; a flame can be immediately doused with a properly functioning fire extinguisher.