How should a kill cord be used?
Short answer
Attached to the driver before starting when the boat is fitted with one
A fitted kill cord must protect the current driver whenever the engine runs; test it and stop the engine before transfer. Revise kill-cord-discipline.
Sources and scope
Reviewed by Richard Moore on . This answer is scoped to united kingdom and general recreational seamanship; check the current chart, publication, local rules and official operational guidance before acting afloat.
Quick check
How should a kill cord be used?