Electrical Isolation Incident

Permit to Work and Isolation Incident

• An electrician attempted to install fuses on a live 930V DC electrical system
• The work was on under deck carousels, which were mechanically and electrically isolated for maintenance
• other vessel system were powered from the same cabinet
• Electrical isolation involved removing fuses for the carousel drive unit
• The vessel was in port, and other systems weren't powered by the drive cabinet when fuses were initially removed
• The electrician isolated the entire drive cabinet by isolating breakers and removing fuses
• Fuses were left at the bottom of the cabinet without tags, and the cabinet was unlocked
• A second electrician re-installed fuses, believing the cabinet was isolated
• The second electrician opened the cabinet, removed the protective mesh, and used a 1000V-rated fuse insertion tool
• An arc flash occurred, and the fuse blew during insertion of the second fuse, but no one was injured

Factors contributing to the incident

• No Permit To Work (PTW) was in place
• The work team failed to apply the required level of electrical work and isolation controls
• Isolations were incorrectly applied
• The Vessel Standard Operating Procedures (SOP) did not consider long-term isolations
• The procedure did not protect multiple workers in the area
• Security of the electrical cabinet was not in accordance with procedures
• The electrician did not lock or tag the cabinet when fuses were removed
• Additional work team isolation requirements from the Toolbox Talk (TBT) were not carried out
• The electrician reinstating fuses did not verify power isolation, ignoring cabinet instructions

Actions to be taken

• Review procedures, work instructions, and risk assessments for Permit to Work and electrical isolations
• Review Toolbox Talks to include all aspects of work including PTW and isolations
• Verify the system is isolated BEFORE starting work
• Follow workplace instructions and warning signs

MSF: LTI – Fall from Height

• A Marine Safety Forum Safety Alert 21-18 describes a fall from a bridge deck
• Two teams totaling four crew members maintained the vessel's superstructure
• One team worked on the monkey island, while the other removed gratings and worked on bridge level gantry steel
• The monkey island team moved to the bridge level after finishing and a team member removed his safety harness
• Spotting a paint drip, the team member checked around the bridge before break
• Due to limited space, they moved backwards without looking and not confirming location of the other team
• They stepped back and fell 3m through the grating opening to the boat deck causing a lost time injury

Causes for the fall from height

• Work and Permit to Work Systems not implemented properly
• Lack of situational awareness, risk perception, SIMOPS awareness, or communication
• No barriers or signage was placed around the incident area
• The bridge gantry gratings had been removed which introduced a fall hazard

Action To Take

• Conduct more thorough toolbox talks and pre-task risk assessments for non-routine tasks
• Implement a more thorough approach to SIMOPS
• Identify combined operations and additional hazards introduced by SIMOPS during work planning
• Evaluate if SIMOPS can be avoided and tasks performed at different times
• Evaluate the level of risk associated with SIMOPS
• Determine if planned control measures are adequate, identify additional risk reduction, and update assessments
• Keep a record of incidents to prevent recurrence and input changes into the Permit to Work process

UK HSE: Poor control of work

• A supervisor was sentenced for safety breaches after a worker became entangled in a conveyor belt
• The worker sustained serious injuries to their hand and arm

Events that led to the incident

• A worker repaired a damaged conveyor belt
• The conveyor line started moving as they started work and their arm became entangled
• The entanglement caused muscle and tissue damage

Causes of the incident included

• The site supervisor, responsible for the Permit to Work and isolating the line, was distracted
• The Permit to Work and isolation were not completed
• The conveyor belt restarted during repair work, injuring the employee
• Not implementing company policy for Permits to Work and isolation

Corrective action

• Follow correct control measures and safe work practices to easily avoid incidents

Fractured finger

• A crew member injured their finger while working on deck and handling metal plates
• The incident resulted in a distal fracture, a laceration, and required stitches

Problems that caused the incident

• Heavy weather damaged welded deck plates
• As IP and another crew member handled the plate, the finger got pinched between the plate and the frame
• An X-ray revealed a distal fracture requiring diagnosis
• 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 and not task-specific
• The JSA was for hot work and did not include manual handling

Lessons learned

• Modify the plate with temporary handles to keep fingers away from pinch points
• Use magnetic lifting handles
• Modify generic risk assessments or use dynamic risk assessments/toolbox talks for thorough review
• Use toolbox talks or JSAs to define and understand risks when tasks are slow, uncomfortable, or inconvenient

UK HSE: Liquid petroleum gas (LPG) leak

• The largest UK oil refinery was fined after a worker discovered an LPG leak while cycling home
• 15 tonnes of LPG released uncontrolled near a roadway used by LPG tankers in Fawley, Hants, UK
• The leak went undetected for approximately four hours
• On-site emergency personnel took a further hour to establish the source and reset the valve

Cause of the Gas leak

• LPG ran through the pipe work at too high pressure
• No process detected the flow discrepancy
• The company failed to prevent a major incident

Corrective action

• Implement measures proportionate to the risks
• Implement layers of protection to prevent incidents where handling large amounts of hazardous substances is required
• A number of layers either failed or were not in place which resulted in a significant leak
• Maintaining layers of protection and preventing major leaks is important