courtesy light

Courtesy lights are used to request right-of-way primarily by volunteer or on-call firefighters, emergency medical technicians (EMTs), and other first responders to expedite their response in their privately owned vehicles to their firehouse, base, or directly to the scene of an emergency call. Courtesy lights sometimes allow the user to disobey traffic laws such as speed limits, but usually not laws applying to stop signs or stop lights. Courtesy lights should not be confused with emergency warning lights used in conjunction with audible warning systems (sirens) for emergency vehicles such as police cars, fire apparatus, ambulances, etc, nor should they be confused with warning lights as used by tow trucks, snow plows, construction vehicles and school buses to increase awareness especially when moving slowly or stopped in the roadway.

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