(1) You must ensure that an internal examination of cylinders and shells to be tested is made prior to the hydrostatic tests in addition to an external visual examination.

(2) You must ensure that portable fire extinguishers are hydrostatically tested whenever they show new evidence of corrosion or mechanical injury.

(3) You must ensure that hydrostatic tests are performed on extinguisher hose assemblies which are equipped with a shut-off nozzle at the discharge end of the hose. The test interval shall be the same as specified for the extinguisher on which the hose is installed.

(4) You must ensure that carbon dioxide hose assemblies with a shut-off nozzle are hydrostatically tested at 1,250 psi (8,620 kPa).

(5) You must ensure that dry chemical and dry powder hose assemblies with a shut-off nozzle are hydrostatically tested at 300 psi (2,070 kPa).

(6) Hose assemblies passing a hydrostatic test do not require any type of recording or stamping.

(7) You must ensure that hose assemblies for carbon dioxide extinguishers that require a hydrostatic test are tested within a protective cage device.

(8) You 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 which comply with 29 C.F.R. 173.34 (e)(15) may be hydrostatically tested every ten years.

(9) You 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.

(10) You must ensure that acceptable self-generating type soda acid and foam extinguishers are tested at 350 psi (2,410 kPa).

(11) You must not use air or gas pressure for hydrostatic testing.

(12) You must remove from service and from the workplace extinguisher shells, cylinders, or cartridges which fail a hydrostatic pressure test, or which are not fit for testing.

(13) You must meet the following requirements for gas cylinders:

(a) The equipment for testing compressed gas type cylinders must be of the water-jacket type. The equipment must be provided with an expansion indicator which operates with an accuracy within 1% of the total expansion or 0.1 cc (.1 mL) of liquid.

(b) The equipment for testing noncompressed gas type cylinders must consist of the following:

(i) A hydrostatic test pump, hand or power operated, capable of producing not less than 150% 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.