Mercury 4 Manual page 15

Avoid the combination of a running engine and poor ventilation. Prolonged exposure to carbon monoxide in
sufficient concentration can lead to unconsciousness, brain damage, or death.
GOOD VENTILATION
Ventilate passenger area, open side curtains, or forward hatches to remove fumes.
POOR VENTILATION
Under certain running and/or wind conditions, permanently enclosed or canvas enclosed cabins or cockpits with
insufficient ventilation may draw in carbon monoxide. Install one or more carbon monoxide detectors in your boat.
Although the occurrence is rare, on a very calm day, swimmers and passengers in an enclosed area of a stationary
boat that contains or is near a running engine may be exposed to a hazardous level of carbon monoxide.
WHILE BOAT IS STATIONARY
a
a - Running the engine when the boat is moored in a confined space.
b - Mooring close to another boat that has its engine running.
WHILE BOAT IS MOVING
a
a - Running the boat with the trim angle of the bow too high.
b - Running the boat with no forward hatches open.
GENERAL INFORMATION
WARNING
!
Example of desired air flow through the boat.
b
11
ob00316
ob00317
b
ob00318