It's the Law: Required Equipment

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 gasoline-powered vessels, constructed in a way that would entrap fumes, must have at least two ventilation ducts fitted with cowls to remove the fumes.
• 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 or "ski craft"), open the engine compartment and sniff for gasoline fumes before starting the engine.

Backfire Flame Arrestors

Backfire flame arrestors are designed to prevent the ignition of gasoline vapors in case the engine backfires.

• All powerboats (except outboards) that are fueled with gasoline must have a USCG—approved (must comply with SAE J-1928 or UL 1111 standards) backfire flame arrestor on each carburetor.
• Backfire flame arrestors must be in good, serviceable condition and be mounted with metal-to-metal contact.
• It is illegal to have any holes in the mesh of the backfire flame arrestor.

Mufflers and Noise Level Limits

All vessel engines must be equipped with an effective muffling device or underwater exhaust.

The noise level of any motorized vessel must not exceed these limits.

• Stationary test limit:
  • 90 decibels for engines manufactured prior to January 1, 1991
  • 88 decibels for engines manufactured on or after January 1, 1991
• Moving test limit as measured on the "A" scale and from a distance of 50 feet:
  • 84 decibels for engines manufactured prior to January 1, 1991
  • 82 decibels for engines manufactured on or after January 1, 1991

It is illegal to own or operate a vessel that exceeds the decibel limit or a vessel that is equipped with a device that adjusts the muffling device.