Your boat must have a Back-Fire Flame Arrestor (BFA) mounted to each carburetor if it is gasoline-powered and have an inboard engine installed after April 1940. This device will help to muffle a spark in an enclosed engine space and prevent fires. The BFA must be in good working order and be firmly attached to the air intake with a flame-tight connection. However, this Coast Guard requirement does not apply to boats with outboard engines.

Your Back-Fire Flame Arrestor is only valid if it is:

• Coast Guard-approved or,
• approved by SAE J-1928 (Society of Automotive Engineers Standard) or,
• approved by UL 1111 (Underwriters Laboratories).

Note: Outboard engines are not required to have a BFA, however most do have a built-in form of back-fire flame control protection. For example, outboard engines often have a ‘reed-type’ carburetor attachment and PWCs use an air induction system to prevent fires.

Cleaned and checked your BFA regularly to keep it in good working order. Clean it by removing it from the boat and washing off any gas residue with mild soap and water. Check for any visible damage once it’s clean. Remember to reattach the BFA correctly after you’ve cleaned it.

A ventilation system circulates fresh air on your boat. Ventilation will remove gas fumes from the hull and engine compartments, which will help prevent a fire or explosion from occurring. Ventilation ducts must be positioned above the bilge line and in the lower portion of the compartment. This is because gases are heavy and tend to accumulate near the floor.

Importantly federal law requires any boat powered by gasoline and built after April 25^th, 1940, to have a ventilation system in place.

Your boat has either a natural or a powered ventilation system, depending on the engine type and the year it was made.

Natural Ventilation System:

A natural ventilation system has two ventilation ducts with cowls. These are hooded openings that scoop up the air from outside.

Powered Ventilation System:

Boats built later than July 31, 1982 that have an inboard engine or installed fuel tanks must have a powered ventilation system. The ventilation system must consist of one or more exhaust blowers. 

Maintain the ventilation system by regularly checking that the vents are free of obstacles. Take a close look at the device. Does any part of the system look worn or in need of being replaced? Turn on the blower to check that the powered system is functioning properly, if you have a powered ventilation system.

Note: The USCG recommends that a powered ventilation system be turned on four minutes before starting your boat’s engine and for at least four minutes after you’ve fueled your boat. This will clear out any fumes that may have settled.