The NFPA 10 Standard for Portable Extinguishers has been revised and released, the standard now includes requirements to remove and replace outdated extinguishers. NFPA 10, 2007 edition states "Dry chemical stored pressure extinguishers manufactured prior to October 1984 shall be removed from service at the next 6 year maintenance or the next hydrotest interval, whichever comes first.".

Extinguishers NOT considered stored Pressure are:

Carbon dioxide Fire Extinguishers are not considered stored pressure. Per NFPA 10 a carbon dioxide extinguisher is classified as a self-expelling type of extinguisher.

Other extinguishers that are not considered stored Pressure are: Pressurized Water, Cartridge Operated extinguishers , Clean agent extinguishers, foam extinguishers or anything other than stored pressure dry chemical extinguishers. Although this may change in some future edition of NFPA 10, but for now it only applies to stored pressure dry chemical extinguishers manufactured prior to October 1984.

The following types of fire extinguishers are considered obsolete and shall be removed from service:

(1) Soda Acid
(2) Chemical Foam (excluding film-forming agents)
(3) Vaporizing liquid (e.g., carbon tetrachloride)
(4) Cartridge operated water
(5) Cartridge operated loaded stream
(6) Copper or brass shell (excluding pump tanks) joined by soft solder or rivets
(7) Carbon dioxide extinguishers with metal horns
(8) Pressurized water fire extinguishers manufactured prior to 1971
(9) Solid charge-type AFFF extinguishers (paper cartridges)
(10) Any extinguisher that needs to be inverted to operate
(11) Any stored pressure extinguisher manufactured prior to 1955
(12) Any extuinguisher with 4B, 6B, 8B, 12B, ans 16B fire ratings
(13) Stored-pressure water extinguishers with fiberglass shells
pre-1976)

The 5 new categories are items: 8, 10, 11, 12 and 13 , these are added to the NFPA 10, 2007 as new categories.

Any Extinguisher that can no longer be serviced in accordance with the manufacturer's maintenance manual is considered obsolete and shall be removed from service. (NFPA 10, 2007, 4.4.2)

Meaning that if the extinguishing agent or parts , either manufacturers's recommendend replacement parts or parts specifically listed for use in the fire extinguisher are not available, then the extinguisher cannot be serviced according to the manufacturer's manual.