Do ammonium phosphate and CO2 in fire extinguishers expires and when?

Answer 1

Well in theory, a CO2 extinguisher could stay "charged" indefinitely. However, the shell itself will come due for a hyrdostatic test every five years.

Dry Chemical Extinguishers only come due for a hydro-test every twelve years. However, stored pressure units have to be emptied, examined on the inside, and recharged every 6 years.

All extinguishers should be inspected by a competent or certified inspector at least annually.

Answer 2

As far as what is in the extinguisher, it shouldn't. It needs to be checked every year to be sure it stays charged. Dry Chem ext. should be turned upside down and tapped with a hand or rubber mallet to be sure the powder is loose if they aren't serviced by someone. Most of your household extinguishers are cheaper to replace than to have them serviced if the are under charged.