Pressure vessels hazards and safety

1. What is a pressure vessel?

2. Do I need to do anything special/extra if I have a pressure vessel?

3. If I answer yes to question the question above, what are the special/extra things that I need to do?

What is a pressure vessel? Luckily AS/NZS 1200:2000  Pressure equipment has a definition for us.

Pressure vessel—a vessel subject to internal or external pressure. It includes interconnected parts and components, valves, gauges and other fittings up to the first point of connection to connecting piping.

Simple enough. Vessels subject to internal pressure such as gas cylinders & air compressor receivers and those subject to external pressure such as vacuum tanks are all pressure vessels.

Do I need to do anything special/extra if I have a pressure vessel? Not all pressure vessels are subject to the requirements as defined in Australian Standards. Only vessels with a certain combination of pressure and diameter are required to comply with the requirements of the relevant Australian Standard.

Here are the graphs that you can use to determine whether or not your vessel is subject to these requirements.

For vessels subject to internal pressure. Simply plot your pressure/diameter on the graph. If the point is above the line then your vessel is subject to the requirements of the relevant standard.

For vessels subject to external pressure. Simply plot your pressure/diameter on the graph. If the point is above the line then your vessel is subject to the requirements of the relevant standard.

Tips:

• All vessels with a design pressure over 50 kPa are pressure vessels are subject to the requirements of the relevant Australian Standard.

• If a manufacturer declares that there vessels are not pressure vessels because they don’t meet the definition as per SAE or ASTM don’t assume that their vessel is not subject to the relevant Australian Standard. SAE & ASTM are American standards.

Now that we have established that you have a pressure vessel subject to the requirements of the relevant Australian Standards, what are the requirements? The short answer is that pressure vessels will require –

• A manufacturer’s plate with specific information marked upon it

• A pressure gauge and

• An inspection regime to be completed and documented.

There may be other requirements depending on the contents of the vessels and the hazard level of the vessel. The specifics of these requirements are included in Plant Assessor assessment surveys for the individual machines.

Please contact the team at Plant Assessor if you have any queries about pressure vessels or indeed any other technical queries.