September 26, 2016

Hydrostatic Testing

Hydrostatic Testing

Hydrostatic testing

image of hydrostatic testing

Fire Safety OSHA Regulation 29 CFR 1910 Subpart E

• Part Title: Occupational Safety and Health Standards


Subpart Title: Exit Routes, Emergency Action Plans, and Fire Prevention Plans

The above is from the OSHA Regulation 29

How does hydrostatic testing work?

To understand how hydrostatic testing is used to check a cylinder and/or hose assembly for leaks or flaws, let’s take a look at the procedure.

First, the extinguisher valve is removed and the threads and interior of the cylinder are checked for corrosion, pitting, and any other abnormalities.  

Types of Hydrostatic Tests:

Hydrostatic Test Pump
The hydrostatic test described above is called the water jacket type because the cylinder is enclosed and surrounded by water during the testing process. All compressed gas type cylinders (CO2, dry chemical, etc.) must be hydrostatically tested using this method. They must also have an expansion indicator that operates with an accuracy within one percent of the total expansion or .1cc (.1mL) of liquid. 

For all non-compressed gas type cylinders, you can use a manual or powered hydrostatic test pump as long as it meets the following requirements 

It must be capable of producing at least 150 percent of the test pressure, and include the appropriate check valves and fittings. 


To ensure that your extinguisher will operate effectively and safely, you are required to have them hydrostatically tested: either every five or 12 years, depending on the type of extinguisher. 
Whenever they show new evidence of corrosion or mechanical injury. 
It is illegal and dangerous to perform a hydrostatic test on any cylinder or shell without first doing a visual external and internal examination. If any component exhibits at least one of the following conditions, it must be removed from service immediately. 
Hydrostatically test portable extinguishers at the intervals listed  except under any of the following conditions: