You need to engage an Authorised Examiner to conduct periodic examinations and tests on your Pressure Vessel to ensure the integrity of the vessel.
Your Pressure Vessel must be examined at regular intervals by an Authorised Examiner or MOM-authorised boiler inspector, as stipulated in the Workplace Safety and Health (General Provisions) Regulations.
The table below shows the types of pressure vessels, examinations and tests intervals and types of examinations and tests required:
| Type of vessel |
Examinations and tests interval |
Type of examinations and tests |
| Steam boiler |
Every year |
Visual examination and running tests. |
| Air receiver, steam receiver |
Every 2 years |
Visual examination and running tests. |
| Autoclaves |
Every 2 years |
Visual examination and running tests. |
| Autoclaves |
Every 6 years |
Visual examination on the surface of the external shell. The insulation must be removed completely. |
| Steam receiver, packaged fire-tube boiler |
Every 10 years |
Visual examination on the surface of the external shell. The insulation must be removed completely. |
| All types as listed above |
Every 10 years |
At least one hydrostatic test and thickness gauging must be conducted to ensure the integrity of the Pressure Vessel. |
With effect from 5 Aug 2023, owners will no longer receive notifications to remind them of examinations and tests of pressure vessels that are due. Owners should keep track of the examination and test due dates in the Reports of Examination, and engage an Authorised Examiner to carry out the necessary examinations and tests before the due dates.
A Steam boiler is defined as an Autoclave if it meets all of the following criteria:
- It uses electricity as the only form of power.
- It has a maximum steam volume of maximum 40 litres.
- It has a safe working pressure of maximum 4 bars.
- Water is fed manually at the start of the steam generation process. It must not be fed continuously from a potable water main.