Pressure Vessel Safety
Pressure vessels store gases or liquids under pressure and must be designed, built and recurringly inspected according to their hazard category, since material failure, corrosion or a failed pressure relief device can trigger a sudden release of stored energy.
Hazard picture
If a pressure vessel shell fails, the stored compression energy is released suddenly; vessels with flammable or toxic contents add a substance hazard on top. Failures are usually caused by material or weld defects, external or internal corrosion, fatigue from pressure cycling, and an undersized or blocked relief device. Classification into hazard categories based on the product of pressure and volume determines which design, testing and certification requirements apply.
Protective measures
The basis is code-compliant design and manufacture with documented material testing and weld qualification, complemented by correctly sized safety relief valves or rupture discs. Recurring internal and external inspections by accredited bodies - including wall thickness measurement for corrosion-prone vessels - detect material loss before the remaining load-bearing capacity becomes critical.
Insurance relevance
For machinery insurance, key criteria for pressure vessels are age, inspection history and whether current operating parameters still match the original design basis. Undocumented modifications, overdue inspection intervals or a blocked relief device are regarded as serious deficiencies with a direct bearing on explosion risk.
Legal basis
- EU: Directive 2014/68/EU (Pressure Equipment Directive) on the Making Available on the Market of Pressure Equipment
Standards and codes
- DS 12-2 – Vessels and Piping
- DS 12-43 – Pressure Relief Devices