Regal 3300 Owner's Manual page 107

Gas Vapor Detector
bilge of the boat for gas fumes or signs of a fuel leak before starting
the engines. If uncertain, consult a marine service professional.
https://www.boat-manuals.com/
Engine & Controls
If equipped, the gas vapor detector
determines if there is a level of
gasoline vapors that is unsafe in the
engine room of the boat. If installed,
turn on the unit and wait about one
minute for it to do its safety test. If all
is well it will display a green light. You
must run the test before you start the
engines. In the event you don't get a
green light, you must investigate the
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