How long should the post-work fire watch period typically continue after hot work has finished, and why is this duration necessary?

A. No watch is needed after the tools are switched off

B. Exactly 5 minutes is always sufficient regardless of the work or materials involved

C. A defined period (commonly around 30-60 minutes, per the risk assessment/company procedure), because smouldering material inside insulation, lagging, or behind structure can develop into open fire well after the visible work has stopped

D. The fire watch period only matters if the job took longer than 4 hours

A. Any task lasting longer than 30 minutes

B. Only welding using electric arc equipment

C. Any work involving an open flame, welding, burning, grinding, or any process that produces sufficient heat or sparks to act as a source of ignition for flammable materials, gases, or vapours

D. Only work carried out inside a cargo tank

A. A clear radius of at least 10 metres (or as defined by the risk assessment for the specific task and materials), with all combustibles removed or adequately shielded

B. No clearance is needed if a fire extinguisher is present

C. Clearance is only relevant for work carried out in an engine room

D. 1 metre is always sufficient regardless of the work type