What is required on all vessels equipped with carburetors, excluding outboards?

Vessels equipped with carburetors, excluding outboards, are required to have a backfire flame arrestor as a safety feature. This device is designed to prevent flames from escaping the engine's intake manifold in the event of backfire, which can pose a significant fire hazard. The backfire flame arrestor allows air to enter the carburetor while restricting any flames from exiting, thus reducing the risk of explosion or fire on the vessel. This requirement is in place to protect both the vessel and its occupants from potentially catastrophic incidents.

While other safety equipment like fire extinguishers, carbon monoxide detectors, and life vests are essential for overall safety on boats, they do not specifically address the hazards associated with carbureted engines. Fire extinguishers are generally required for all vessels but are not specific to the dangers presented by carburetors. Carbon monoxide detectors help in monitoring harmful gas levels, and life vests are crucial for personal safety, but they do not mitigate the risk of fire directly related to carburetor operation.