Pressure vessels are potentially dangerous units and are subject to a range of safety regulations – particularly governing pressure relief. The following regulations apply to all pressure vessels used in the UK and the EU. Other regulations may apply to vessels sited in other jurisdictions, so for such jurisdictions we recommend you speak with one of our design engineers to ensure compliance before you proceed with a design.
Compliance is far easier to implement at the design phase than it is in retrospect!
Simple Pressure Vessels Directive (87/404/EEC)
The Simple Pressure Vessels Directive (SVPD) is a general set of regulations for pressure equipment placed on sale in the UK or the EU. Manufacturers are obliged to mark their pressure vessels with the CE mark, which indicates they are safe for sale and meet the required standards. The SPVD was incorporated into UK law in 1991 as the Simple Pressure Vessels (Safety) Regulations.
According to the regulations, a ‘simple pressure vessel’ is one which:
- Contains atmospheric air or nitrogen at pressures between 0.5 bar and 30 bar.
- Is not exposed to naked flames or extreme heat.
- Is part of a series of pressure vessels sharing the same design – i.e. not a bespoke vessel.
- Is constructed of welded non-alloy aluminium or steel.
- Has a working temperature range of -50°C to 300°C for steel, and -50°C to 100°C for aluminium pressure vessels.
- Is cylindrical in shape with a circular cross-section.
- Is not intended for use with nuclear or radioactive materials.
- Is not intended for use on aircraft or merchant shipping vessels.
Pressure Equipment Regulations 1999 (PER)
The PER regulates the design and manufacturing quality of pressure vessels and related equipment, including pipes, safety equipment, storage tanks, couplings, flanges etc. Each regulation ensures that operational safety is built into the design and testing of pressure vessels. The PER is the UK’s harmonised version of the European Commission ATEX Products Directive. It incorporates the Pressure Equipment Directive (Directive 97/23/EC) and the European Pressure Equipment Regulations (SI 1999/2001). Special attention is given to pressure vessels operating at high pressure and those using potentially explosive fluids.
Pressure Systems Safety Regulations 2000 (PSSR)
The PSSR deals with ensuring personal safety when handling pressurised fluids of 0.5 bar or more above atmospheric pressure. For each qualifying piece of equipment, a written scheme of examination (WSE) must be instigated and carried out by an independent competent person. The competent person can be employed in-house, but must be independent of the day-to-day functioning of the equipment.
The PSSR governs pressure systems which store energy within the system itself. This applies to many but not all pressure vessels. To determine whether or not your pressure vessel falls under the PSSR remix, please refer to the PSSR Approved Code of Practice, which can be downloaded here.
Enforcement & Compliance
Pressure safety regulations in the UK are enforced by the Health & Safety Executive (HSE), which expects owners (and primary users) of pressure equipment to appoint appropriate competent persons and conduct comprehensive risk assessments for all pressurised units.
These regulations apply to some vessels but not others, so please take time to understand your health and safety requirements before commissioning a pressure vessel. Our design engineers can guide you through your compliance requirements and make you aware of your responsibilities.
Compliance generally involves completing a WSE for each piece of pressure equipment at set regular intervals. The WSE should explain:
- The vessel’s suitability for its intended use.
- Repairs or maintenance required.
- Risks associated with the vessel and actions taken to minimise and counteract these risks.
- Any imminent dangers and actions taken to prevent vessel failure.
Minimising Risk, Maximising Performance
Our pressure vessels are fully compliant with all safety regulations relevant to where the equipment will be used. Our design plans take into account possible relocation and go beyond compliance to ensure maximum safety and minimal risk to operators and property. For more information please call our team on +44 (0) 1656 750262.