Trigonometry

IMCA Safety Flashes summarize key safety matters and incidents to share lessons. Information is anonymized.

An electrician installed fuses on a live 930V DC electrical system.
Under deck carousels were mechanically and electrically isolated for maintenance.
Other vessel systems were powered by the same drive cabinet.
Electrical isolation was done by removing fuses for the carousel drive unit.
The vessel was in port when fuses were first removed, no other systems were powered.
The electrician isolated the drive cabinet by isolating breakers and removing fuses.
The fuses was left at the bottom of the cabinet, and it was left unlocked without tags.
Another electrician re-installed the fuses believing the power was isolated.
The second electrician opened the cabinet, removed the protective mesh, and installed fuses with a tool rated to 1000V.
An arc flash occurred when inserting the second fuse, causing it to blow, but without injury.
There was no Permit To Work (PTW) to control and coordinate activities.
Personnel in different roles did not understand the required electrical work and isolation controls.
The vessel's Standard Operating Procedures (SOP) did not account for long-term isolations.
Procedures were not followed, as the electrician did not lock and tag the cabinet per company rules.
The re-installing electrician did not check if the power was isolated, ignoring cabinet instructions.

Review procedures, work instructions, and risk assessments for Permit to Work and electrical isolation.
Review Toolbox Talks to cover all aspects of work with PTW and isolations.
Check the system is isolated BEFORE starting work.
Follow workplace instructions and warning signs, ask if unsure.

Four crew in two teams maintained the vessel superstructure, one team on the monkey island, the other on the bridge level gantry.
After finishing on the monkey island, one team member removed his harness to address a paint drip.
The team member moved backwards to address the paint drip without checking behind.
The team member fell 3m through a grating opening to the boat deck, resulting in an LTI.
The Control of Work and Permit to Work Systems were not effectively implemented.
Lack of situational awareness, SIMOPS awareness, and communication between deck personnel.
No barriers or signage were in the incident area, and the bridge gantry gratings were removed.

Improve toolbox talks and pre-task risk assessments, especially for non-routine tasks.
Improve SIMOPS (Simultaneous Operations) approach.
Identify combined operations and hazards during scope of work planning.
Always consider: Can SIMOPS be avoided by executing tasks at different times?
Assess risk level and ensure the planned controls are adequate, add more if necessary.
Keep a record to prevent recurrence, input to the Permit to Work / Control of Work process, and "embed" any changes identified.

A supervisor was sentenced for safety breaches after a worker became entangled in a conveyor belt, sustaining serious injuries.
A worker repaired a damaged conveyor belt.
The conveyor line started moving, entangling the worker's arm.
The site supervisor was responsible for the Permit to Work.
The supervisor was distracted and did not complete the Permit to Work or isolate the line.
The inspector noted the supervisor failed to implement company policy for Permits to Work and isolation.

A crew member suffered a pinch injury to his finger while working on deck.
The plate was being re-positioned due to damage from heavy weather.
The finger was trapped between the plate and frame, resulting in a distal fracture.
The plate design did not allow safe manual handling.
The plate installation had a permanent risk of finger entrapment.
Risk assessments and toolbox talks were generic in content and not task-specific.
The JSA did not include manual handling.
Modify plates to have temporary handles to create safety by design.
Long term solutions: Magnetic lifting handles sourced.
Modify or specifically tailor generic risk assessments to the task.

The operator of the UK's largest oil refinery was fined for health and safety breaches after a LPG leak.
15 tonnes of LPG was released through a valve near a roadway.
The leak went undetected for around four hours discovered by an employee.
The leak source took another hour to establish to reset the valve.
LPG was put through the pipe work at too high a pressure for the valve.
There was no process to detect the discrepancy in the flow in the pipe.
The company failed to take all measures necessary to prevent a major incident.
Measures to prevent incidents should be proportionate to the risks.
Companies handling large quantities of substances need layers of protection.
A number of those layers failed or were not in place resulting in a significant leak.
Even though there was no fire or injury, there was potential for a major incident.
Prosecution highlights the importance of maintaining layers of protection and preventing major leaks.