Shell Safety Failings Linked to Violent Propane Release at Marine Terminal

Brief Summary

An employer was prosecuted after an incident at a marine terminal where liquid propane was released without warning during loading operations, creating a rapidly expanding flammable vapour cloud. Injuries were serious and the investigation found major weaknesses in the employer system of work and in how it assessed and implemented changes when replacing loading arms.

What Was The Incident?

In the early hours of 1 November 2018 at a marine terminal, liquid propane was released during ship loading operations. The release was triggered when a technician accidentally pressed a button on a remote control handset, which caused a loading arm quick release coupling to disconnect before the loading arm had been fully cleared of propane. An estimated 250 to 300 kilograms of liquid propane was released at pressure within seconds. The resulting flammable vapour cloud rapidly expanded, enveloping people on the ship deck and on the adjacent jetty.

What Was The Outcome?

The employer pleaded guilty to breaching Control of Major Accident Hazards Regulations 2015 regulation 5(1) and the Health and Safety at Work etc Act 1974 section 33(1)(c). It was fined £450,000. The HSE enforcement included an Improvement Notice that prompted a post incident review by the employer, which identified that a coupling interlock was technically feasible and reasonably practicable.

Key Points To Consider

Do not reuse procedures without re validating against the new equipment. The investigation found the operating procedure required disarming an emergency release coupling too early in the disconnect sequence, creating a dangerous window. That procedure also contradicted the loading arm manufacturer guidance and installation related procedures.

Treat equipment replacement as a genuine change, not like for like. When new marine loading arms were introduced, the employer treated the work as a straightforward replacement, even though the new system operated differently and used remote control and a quick release coupling.

Carry out a full risk assessment for new hazards introduced by the change. The new loading arms introduced a remote control handset with exposed coupling buttons on its side. The employer did not consider basic protective measures such as interlocks to prevent coupling opening while propane was still present, or shielding to reduce accidental activation.

Use the change process to close the specific failure pathways. The post incident review confirmed a coupling interlock could have prevented the incident. Change management should focus on eliminating or controlling the exact mechanisms that can create unplanned release during operation.

Plan for major accident scenarios during routine operations. The vapour cloud extended along the length of the ship and across the jetty and could travel significant distances to an ignition source. Systems should assume ignition is possible and ensure controls prevent release and protect people from exposure to flammable vapour.

HSE Prosecution Link