Such a device is called a siren.
All vessels are required to have a sound producing device, such as a horn, whistle, or bell, that can be used to signal warnings or communicate with other vessels on the water.
Red ones!
whistle or horn
If your vessel is less than 39.4 feet long and operating on Pennsylvania state waters, you are required to carry a sound-producing device such as a whistle, horn, or bell. This device should be capable of producing an efficient sound signal to alert other boaters, especially in situations where visibility is reduced. It's essential to have a device that can be heard clearly over the ambient noise, ensuring safety on the water.
Speaker (!?) Plus, I would use the phrase sound waves instead of sound energy.
A whistle or some other mechanical means (horn) to make a sound AND a bell
In Pennsylvania state waters, all vessels are required to carry some type of sound-producing device, such as a whistle, horn, or bell. This regulation applies to motorboats, sailboats, and other vessels, particularly those over a certain length. The sound-producing device is essential for signaling in situations where visibility is limited or to communicate with other vessels. Compliance with this requirement helps promote safety on the water.
A sound-producing device that must be carried on board a boat is a whistle or horn. This device is essential for signaling and communication, especially in situations where visibility is low or to alert other vessels of your presence. Regulations may vary by location, so it's important to check local maritime laws for specific requirements.
It can be, meaning either a sound or a device for producing it. It is also a verb meaning to make a whistling sound.
whistle or horn AND a bell
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