Pressure Vessels that need to be registered
In accordance with the Workplace Safety and Health (General Provisions) Regulations, you must register the following types of Pressure Vessels:
- Air receivers (AR)
- Steam receivers (SR)
- Refrigeration plant pressure receivers (PR)
- Steam boilers, including autoclaves (BR)
- Economisers (BE)
- Superheaters (BS)
- The exact definitions of a Pressure Vessel can be found in the Workplace Safety and Health Act. The exact conditions for registering a Pressure Vessel can be found in Regulation 27 of the Workplace Safety and Health (General Provisions) Regulations.
- Pressure vessels of types BR, BS and BE with a heating surface of more than 1,000 square metres must be examined and registered by MOM-authorised boiler inspectors.
- Heating surface is defined as the total surface of all plates and tubes exposed to heat on one side, and in contact with water on the other. It is measured on either the water or fire side, depending on which side has a greater heating surface (excluding the heating surface of any economiser and superheater connected to the boiler).
Pressure Vessels that don't need to be registered
You do not need to register the following types of Pressure Vessels:
- Pressure vessels that only process chemicals and other substances, not with air, steam or water (when being used as a refrigerant).
- Pressure vessels that operate under vacuum or negative pressure.
- Air receivers, steam receivers or refrigerating plant pressure receivers where the safe working pressure does not exceed 0.5 bar or the product of its safe working pressure and volume does not exceed 100 bar litres.
- Steam boilers where the maximum permissible working pressure does not exceed 0.5 bar.
Regulations, in accordance with the Workplace Safety and Health (WSH) Act, still apply even if your Pressure Vessel is exempted from registration requirements.
Owners of pressure vessels still need to ensure that the equipment is designed and fabricated to relevant internationally recognised codes and standards and properly maintained – WSH (General Provisions) Regulations, Reg 33.
Who can register
As the owner, you must engage an Authorised Examiner to register your Pressure Vessel.
The Authorised Examiner will:
- Conduct necessary tests and examinations.
- Issue an examination report.
- Register the Pressure Vessel on your behalf.
- Create a new non-notifiable workplace to register the Pressure Vessel where necessary.
Find an Authorised Examiner for Pressure Vessel
As the owner, you need to provide the Authorised Examiner with the following documents:
- Construction drawing of the pressure vessel, showing welding details.
- Design calculations (endorsed by the Approved Overseas Inspection Agency) made to either ASME or BSI codes.
- A layout plan of the boiler house or room conforming to SS 567: 2011 factory layout safety health and welfare considerations.
- A steam piping diagram (drawn to ASME 31.1 / 31.3).
- (For fuel or gas or dual-fired steam boilers) Approval letter from the National Environment Agency for installing a chimney and blow-down pit.
- (For gas or dual-fired steam boilers) Gas Train Layout Plan in compliance with BS EN 676 or equivalent.
- (For vessel fabricated overseas) A fabrication survey report by an accredited Inspection Body (IB) certifying that the pressure vessel has been fabricated and tested according to the accepted Pressure Vessel code or standards.
- If using other pressure vessel codes, you must get approval from the Commissioner.
- You must request for a copy of the IB’s accreditation certificate to verify:
- Scope of accreditation, e.g. design verification, fabrication, inspection of pressure vessel.
- The certificate wasn’t expired when the pressure vessel was being fabricated.
- (For vessel fabricated in Singapore) A fabrication survey report from an Authorised Examiner or approved local inspection agency.
You must also keep the documents until the Pressure Vessel is longer in operation.
What is an accredited Inspection Body (IB)
An accredited IB refers to conformity assessment bodies (CABs) accredited to “ISO / IEC 17020 – General Requirement for the Operation of Various Types of Bodies Performing Inspection”.
They’re accredited by the Singapore Accreditation Council (SAC), or SAC’s Mutual Recognition Arrangement (MRA) partners, for design verification and new construction / fabrication inspection of pressure vessel.
See list of national accreditation boards that are signatory to MRA.
As an AE, you can register and manage pressure vessels:
- Register, re-register or transfer a Pressure Vessel.
- Submit a Pressure Vessel examination report.
- Amend a Pressure Vessel examination report.
- View details of registered Pressure Vessels.
Get type approval of Autoclaves
Complete the application form and email all supporting documents to email@example.com.
View additional resources about Pressure Vessels: