You need to refuel your boat. when should you turn on the power ventilation system?

If you need to refuel your boat, you should turn on the power ventilation system at least four minutes both after fueling and before starting your engine to remove gas vapors in the bilge. Some other important things are:
- all fuel lines, connections, and fuel vents must be checked.
- smoking is forbidden 
- never fuel at night unless it is an emergency.
- all windows, ports, doors, and other openings should be closed in order to prevent fumes from entering the boat.

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