Emergency lighting systems – as the name itself implies – are needed when the main power supply trips or fails. There can be different reasons for the failure of the main power supply – like a power cut or a fire. Abrupt termination of power transmission often leads to sudden darkness. The unexpected situation may prove to be dangerous for the occupants. It often triggers chaos and panic. An emergency lighting solution is the best way to avoid such untoward incidents that trigger a sudden power failure.
In the following section of the blog post, let us explore emergency lighting systems – how they are installed, how often they need servicing and other factors.
An emergency lighting system – a brief introduction
It has already been mentioned above, emergency lighting is the variety of lighting that provides illumination and keeps the darkness away in an emergency circumstance. There could be various reasons to trigger the emergency. A fire and a power cut are the most common causes that one comes across for emergency lighting systems to take over. Sudden and unexpected darkness creates panic and in certain situations, it may also turn out to be life-threatening.
In easy and simple words, emergency lighting serves as a backup light source. This backup source illumination automatically takes over control and illuminates an area when the primary lighting system fails. This is how an emergency lighting system saves a building from sinking into complete darkness when the property’s primary lighting system trips. Emergency lighting is necessary for properties where members of the public have access, like certain government offices, hospitals, shopping malls, large auditoriums, and others. It is also a necessity in buildings where people are employed. On the other hand, individual houses and privately occupied flats that are located inside larger residential blocks do not need emergency lighting.
The types of properties that are more likely to have emergency lighting include the following –
- Large shops or departmental storefronts
- Shopping malls
- Leisure centres
- Car parks
- Airport terminals
- Railway stations
- Residential blocks and flats
Emergency lighting deals with the safety of the members of the public. Thus unlike regular lighting, it is regulated by law. There are specific standards that define where and when this kind of lighting is to be installed and the level of illumination it should provide. Even the aspects of servicing and maintenance of this kind of lighting are to be determined carefully keeping the safety of the public in view.
Emergency lighting types
Emergency lighting comes in four different varieties, namely –
High-risk task area lighting – this type of lighting is installed at places that host tasks that involve high risks, like operating machinery. The lighting is kept illuminated for a lengthy period of time so that worker can stop their work, put the tools down, switch the machinery off, and evacuate safely.
Escape route lighting – as it is implied by the name itself, this is exit route lighting. It illuminates emergency exits and fire escapes so that occupants can evacuate a building safely.
Standby lighting – this type of emergency lighting gets switched on automatically in the incident of a power cut. However, unlike other varieties of emergency lighting, this one is not required by legislative provisions. Usually, generators fuelled by diesel keep standby emergency lighting on. Once the main power gets restored, standby lighting is switched off.
Open area emergency lighting – this variety is also referred to as ‘anti-panic lighting’. It is installed in open areas to provide sufficient illumination to facilitate a safe escape during an emergency situation or a fire.
Different types of power supplies for emergency lighting
There are two options to power emergency lighting –
- A self-contained or single-point source of power or
- A central battery sources
A self-contained or single-point power source offers certain benefits which include the following –
- Faster and more hassle-free to install
- More budget-friendly option
- Practically zero maintenance
- No additional wiring or any other hardware required
- Excellent level of integrity as each light is completely independent
- The flexible system can be easily expanded
- Low cost of hardware equipment
- It does not require monitoring for any special subcircuit
- The system automatically triggers illumination whenever the supply from the mains fails
However, the system also has a few flip sides. These include –
- Easily susceptible to weather conditions, like the sun, rain, and storm
- The pretty limited life of its battery
- As every light unit is independent testing of the system requires isolation and individual inspection
Central battery source has some great advantages to offer, like –
- Longer lasting batteries
- In a controlled environment, it proves pretty stable
- Larger batteries used in the system work out cheaper per power unit
- Easy and hassle-free maintenance
- Easy to conduct routine tests
The disadvantages that central battery sources have included –
- Setting up of the system works out to be costly
- The emergency lights that are wired furthest away from the central battery usually show voltage problem
- You need a dedicated ‘battery room’ to work with this system
- A battery or wiring failure may disable a large part of the system from working
- The system may not be able to operate if there is a failure of the mains due to some localized issue
Laws related to emergency lighting in the UK
As far as installing emergency lighting systems in buildings like schools, offices, hospitals, nursing homes, colleges, museums, shops, and multi-story buildings are concerned in the UK, everything is guided by the British Standard BS 5266 – 1.
These standards offer detailed guidance on emergency lighting installation, its application, and practice. The standards duly cover all the relevant aspects including the following –
- Design and installation
- Installation and wiring
- Commissioning and testing
- Minimum duration
- Response times
- The ratio of illumination, glare, and colour
- Maintenance and servicing
By virtue of the Regulatory Reform (Fire Safety) Order 2005 you must put up signs indicating all emergency routes and exits. The emergency lighting system thus installed must provide adequate intensity for the required illumination.