(1) The employer must ensure that a trained person performs hydrostatic testing with suitable testing equipment and facilities.
(2) The employer must ensure that portable extinguishers are hydrostatically tested at the intervals listed in the table below.
Type of Extinguishers | Test interval (years) |
Soda acid (stainless steel shell) | 5 |
Cartridge operated water and/or antifreeze | 5 |
Stored pressure water and/or antifreeze | 5 |
Wetting agent | 5 |
Foam (stainless steel shell) | 5 |
Aqueous film forming form (AFFF) | 5 |
Loaded stream | 5 |
Dry chemical with stainless steel | 5 |
Carbon dioxide | 5 |
Dry chemical, stored pressure, with mild steel, brazed brass or aluminum shells | 12 |
Dry chemical, cartridge or cylinder operated, with mild steel shells | 12 |
Halon 1211 | 12 |
Halon 1301 | 12 |
Dry powder, cartridge or cylinder operated, with mild steel shell | 12 |
Exception: | Extinguishers must not be hydrostatically tested if the following conditions exist: |
| (a) When the unit has been repaired by soldering, welding, brazing, or use of patching compounds; |
| (b) When the cylinder or shell threads are damaged; |
| (c) When there is corrosion that has caused pitting, including corrosion under removable name plate assemblies; |
| (d) When the extinguisher has been burned in a fire; or |
| (e) When a calcium chloride extinguishing agent has been used in a stainless steel shell. |
(3) In addition to an external visual examination, the employer must ensure that the cylinders and shells are examined internally before the hydrostatic testing.
(4) The employer must ensure that portable fire extinguishers are hydrostatically tested whenever they show new evidence of corrosion or mechanical injury.
(5) The employer must ensure that hydrostatic tests are performed on extinguisher hose assemblies that are equipped with a shut-off nozzle at the discharge end of the hose. The test interval must be the same as specified for the extinguisher on which the hose is installed.
(6) Carbon dioxide hose assemblies with a shut-off nozzle must be hydrostatically tested at 1,250 psi (8,620 kPa).
(7) Dry chemical and dry powder hose assemblies with a shut-off nozzle must be hydrostatically tested at 300 psi (2,070 kPa).
(8) Hose assemblies passing a hydrostatic test do not require any type of recording or stamping.
(9) The employer must ensure that hose assemblies for carbon dioxide extinguishers that require a hydrostatic test are tested within a protective cage device.
(10) The employer must ensure that carbon dioxide extinguishers and nitrogen or carbon dioxide cylinders used with wheeled extinguishers are tested every five years at 5/3 of the service pressure as stamped into the cylinder. Nitrogen cylinders that comply with 29 C.F.R. 173.34(e)(15) may be hydrostatically tested every ten years.
(11) The employer must ensure that all stored pressure and Halon 1211 types of extinguishers are hydrostatically tested at the factory test pressure not to exceed two times the service pressure.
(12) The employer must ensure that self-generating type soda acid and foam extinguishers are tested at 350 psi (2,410 kPa).
(13) Air or gas pressure used for hydrostatic testing is prohibited.
(14) The employer must remove from the workplace all extinguisher shells, cylinders, or cartridges that fail a hydrostatic pressure test, or that are not fit for testing.
(15)(a) Water-jacket equipment must be used for testing compressed gas type cylinders. The equipment must have an expansion indicator that operates with an accuracy within one percent of the total expansion or 0.1 cc (.1 mL) of liquid.
(b) The following equipment must be used to test noncompressed gas type cylinders:
(i) A hydrostatic test pump, hand or power operated, capable of producing not less than one hundred fifty percent of the test pressure, which must include appropriate check valves and fittings;
(ii) A flexible connection for attachment to fittings to test through the extinguisher nozzle, test bonnet, or hose outlet, as is applicable; and
(iii) A protective cage or barrier for personal protection of the tester, designed to provide visual observation of the extinguisher under test.
(16) The employer must maintain records of the hydrostatic testing. Their records must include:
(a) The date of test;
(b) The test pressure used;
(c) The serial number, or other identifier of the fire extinguisher that was tested; and
(d) The person or agency performing the test.
The employer must keep the records until the next testing, or until the extinguisher is taken out of service, whichever comes first. The employer must provide us with copies of the records if we ask for them.
