Southern Gas Services became IANZ accredited as a hydrostatic cylinder testing laboratory in 2013, driven by the large number of industrial gas cylinders we have in circulation. Initially, certification was obtained primarily to service our own fleet of cylinders. However, due to increasing demand, we now also provide testing and filling services for customer-owned cylinders.

Our capabilities include the inspection and testing of aluminium and steel high-pressure cylinders, ranging in size from 3L to 80L water capacity and designed for pressures of up to 8000 psig (540 barg).

Under New Zealand law, all gas cylinders must undergo regular inspection and testing to confirm they remain safe and suitable for the storage of high-pressure gases. The required testing frequency depends on the gas type:

• Welding and beverage gases (due to their CO₂ content) require a 5-year test cycle.

• Most other gases, such as argon, follow a 10-year test cycle.

For cylinders over 40 years of age, the testing requirements have been revised. These cylinders default to a 10-year test period, unless they contain carbon dioxide or mixtures with CO₂ at concentrations greater than 25%. In that case, they revert to the 5-year test cycle.

We have state of the art hydraulically driven valving machines, testing rigs and drying racks for fast efficient testing.

– Cylinder collections and delivery of your tested and filled cylinder.
– UV inspection to identify any hydrocarbon contamination.
– Hydrocarbon decontamination using a non-toxic specialised cleaning solution.
– Internal surface cleaning by rumbling with specialised media.
– Safe and legal scrapping of cylinders or valves that do not pass their hydrostatic test.

NOTE: Cylinders MUST be customer owned for us to fill or test and SGSL require proof of purchase.  They CAN NOT be part of another companies rental fleet OR part of a “swap” system.  Our approved fillers & cylinder inspectors must first approve the cylinder as an ownership before we can test or fill it.