• A properly used portable fire extinguisher can often put out an unexpected fire before the flames grow to a level that requires more drastic action. The National Fire Protection Association, or NFPA, establishes rules for fire extinguishers and requires extinguishers to be visually inspected at least every 30 days and professionally maintained annually. The association also requires emptying and recharging every one to six years and hydrostatic testing every five to twelve years. The inspection period depends on the type of extinguisher.
  
  

Monthly Inspection

• The NFPA requires a visual inspection of all fire extinguishers at least every 30 days. It is not necessary for the monthly inspection to be done by a professional. The extinguisher must be checked to make sure that there is no visible or obvious damage, that there is no blockage of the discharge nozzle, that the extinguisher is easily accessible and that it holds a full charge, that there are no broken seals or tamper indicators, and that the instructions and inspection tag are visible and undamaged.
  
  

Annual Inspection

• The NFPA requires that each type of extinguisher be inspected every year by a professional who has been trained and certified and possesses the necessary tools, replacement materials and manuals for the specific type of extinguisher. The inspector will usually attach a tag to the extinguisher to confirm that the inspection has been completed.
  
  

Recharging

• An internal inspection and recharging of the extinguisher must be done periodically by a professional. The inspection period depends on the type of chemical used in the extinguisher, which should be identified on a label. The inspection periods established by the NFPA are: one year for water (stored pressure); three years for AFFF (liquid charge types) and FFFP (liquid charge type); five years for carbon dioxide, dry chemical (stainless steel) and wet chemical; and six years for dry chemical (stored pressure), dry chemical (cartridge), dry powder and halogenated (halon).
  
  

Hydrostatic Testing

• The NFPA also requires periodic professional hydrostatic testing of portable fire extinguishers at either five- or twelve-year intervals. This entails using specialized equipment to pressure test the extinguisher to look for leaks and make sure the extinguisher operates properly at its highest pressure. Five-year testing is required for extinguishers using carbon dioxide, water (stored pressure), dry chemical (stainless steel), wet chemical, AFFF (liquid charge type) and FFFP (liquid charge type). Twelve-year testing is required for extinguishers using dry chemicals (stored pressure and cartridge), dry powder and halogenated (halon).