Emergency lights are lights which are designed to be useful in an emergency. There are a number of different types of emergency lights, ranging from avalanche beacons which are designed to attract the attention of emergency rescuers to the emergency lights used by drivers to alert passerby to the fact that they are experiencing vehicle problems. Lighting systems which work in an emergency can be quite valuable, and it is a good idea to routinely check emergency lighting systems to confirm that they still work.
In the sense of lights built into something like a car, boat, train, or airplane, emergency lights typically run on a separate circuit from the rest of the electronics, and they are designed to keep working even if power is lost, utilizing backup power supplies. Emergency lights on vehicles used for mass transport are often designed to click on in the event of an emergency, illuminating the way to exits so that people will be able to find their way to safety. Emergency lighting can also be used as a warning, as in the case of car emergency lights or “hazards” which are turned on when a car is disabled by the side of the road to alert drivers to the fact that there is a problem.
To differentiate from regular lighting, emergency lighting is sometimes a different color, and it may flash. The different color of the lighting alerts people to the fact that there is an ongoing emergency or problem, with some colors being designed for high visibility, even in conditions where the view is obscured by smoke, dust, and other obstacles.
People also use the term “emergency lights” to refer to portable lighting supplies which are designed for use in an emergency, like candles, hurricane lanterns, and flashlights. These emergency lights can be pressed into service if regular electrical power is lost, and used to help people navigate to safety or just to provide lighting while people wait for power to be restored. Several sources of emergency lighting are strongly recommended for emergency kits, so that lighting will be available in a hurry if it is needed.
Emergency lights can also be designed to be worn. Life jackets and snow gear may be equipped with emergency lights which activate when a button is pushed or a string is pulled, making the wearer easy for emergency services to identify. The use of gear with emergency lights is highly recommended for people going on outdoor adventures, as these lights can be seen from great distances, greatly increasing the chance of rescue in the event of an accident.