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It's the Law

Ventilation Systems


The purpose of ventilation systems is to avoid explosions by removing flammable gases. Properly installed ventilation systems greatly reduce the chance of a life-threatening explosion.

All vessels with gasoline-powered engines operating on federally controlled waters, and constructed in a way that would entrap fumes, must have at least two ventilation ducts fitted with cowls to remove the fumes. On Iowa state waters, every powerboat, except open boats, using any liquid of a volatile nature as fuel, must be provided with the means for properly and efficiently ventilating the bilges of the engines and fuel tank compartments so as to remove any explosive or flammable gases.

If your vessel is equipped with a power ventilation system, turn it on for at least four minutes both after fueling and before starting your engine.

If your vessel is not equipped with a power ventilation system (for example, a personal watercraft), open the engine compartment and sniff for gasoline fumes before starting the engine.

Ventilation system
Properly installed ventilation systems greatly reduce the chance of a life-threatening explosion.

Federally Controlled Waters

Vessels must observe federal requirements on these waters:

  • Coastal waters
  • The Great Lakes
  • Territorial seas
  • Waters which are two miles wide or wider and are connected directly to one of the above