Emergency vehicle equipment
Emergency vehicle equipment is any equipment fitted to, or carried by, an emergency vehicle, other than the equipment that a standard non-emergency vehicle is fitted with (such as headlights, steering wheels, and windshield/windscreens). == Visual warning devices == Emergency vehicles of any kind (fire truck, ambulance, police car) are highly likely to be involved in hazardous situations, including relatively common incidents such as a road traffic collision.
Source: Wikipedia — Emergency vehicle equipment (CC BY-SA 4.0)