Failure of a ½” BSP cap under pressure on well service work
- Safety Flash
- Published on 1 November 1999
- Generated on 11 June 2026
- IMCA SF 06/99
- 1 minute read
The following incident was recently reported to us. It occurred on an offshore installation where the half inch BSP cap appears to have blown off a pressure testing manifold under approximately 1200psi of water pressure.
Our member’s investigation revealed the following:
The cap and BSP/NPT connector were rated to 45000psi. The cap was not found, so the conclusions are based on the following assumptions:
- The cap was not fully engaged.
- It was over-tightened.
The key lessons learned from the incident were identified as:
- Be aware of the ratings, tightening procedures and limitations of all pressure fittings used in a temporary pressure system.
- Pressure fittings should be in good condition prior to use – in particular, threads should be free of paint and debris. If in doubt, use new fittings.
IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.
The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.
All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.
IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.
The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.
Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.