flashing lights and beacons
In the first place, A flashing light displayed on a vehicle, trailer or machinery, can only be blue, red, green, magenta/crimson or amber/yellow.
Indeed, each of the colours, or combinations, conveys a specific warning which we will explain here.
Originally, rotary (or revolving) beacon lights were quite large and used 3 or 4 spot lights attached to a electric motor which rotated.
However, now days, rotating beacons are smaller and weigh a lot less. They are either a Quartz Halogen bulb or LED powered. Both have a rotating reflector to spread the light.
This is the modern LED version:
Combination light bars come in many sizes and variations. Expressly used on Police and Emergency vehicles, they can also be used on security vehicles and tow trucks etc. With this in mind, they cannot be used for road work or construction vehicles. Often, they will include spot lights and sirens. Uniquely, the red and blue colour combinations mast only be used for Emergency vehicles. Examples of Emergency vehicles are:
A red flashing light warns road users of the presence of a vehicle associated with a risk-to-life situation. Importantly, the red lights must only be used when the vehicle is being used for urgent purposes arising from an accident, fire or other emergency. These include:
Generally speaking, an amber flashing light lets road users know there is an obstruction to the flow of traffic. Amber flashing lights may be fitted to vehicles which operate in hazardous situations, and must only be used when the vehicle is standing in a hazardous position or is moving in hazardous circumstances. The light must not operate when the vehicle in a non-hazardous situation.
Similarly, An Amber flashing light can also be used on the vehicles listed here: