Emergency Ex Lighting: All You Need to Know


5 May 2015

Emergency Ex lighting is used to supply back-up illumination in hazardous areas using an in-built battery which provides light output in the event that mains power is lost. This article looks at the advancements in emergency luminaires thanks to the development of LED technology, and explores why they are so important to on-site safety.

Why is Emergency Lighting Important?

Safety is obviously the biggest driver behind the need for emergency lighting. Although the presence of gas or dust denotes a ‘hazardous area’, applications in which Ex lighting is required, such as offshore oil and gas, are also commonly high risk in terms of their general safety and the highest safety measures are required at all times to minimise the risk on-site. Given the dangers during total blackout, a lighting solution which guarantees output even when mains power is down, is critical to safety.

The need for emergency lighting is made greater if a site has an unstable power supply. For example, offshore applications rely on the use of generators as their primary source of power; these generators are often unstable and prone to power outages which increase the reliance on emergency lighting, and make the choice of LED luminaires even more important. With existing technology, even short term voltage drops cause significant disruption given the delay in the luminaire being able to restrike, as previously discussed. An LED luminaire can move seamlessly between mains power and emergency mode, providing the perfect solution to applications with unstable power supplies.

Why LED for Emergency Fittings?

The emergence of LED technology has meant that emergency Ex lighting has become a feasible, functional lighting solution. Although it’s not impossible to find an emergency variant of a  traditional luminaire (i.e. SON or Metal Halide), these units have their limitations.


The size and weight of the emergency batteries tend to be excessive, while they also command a higher cost. As a result, emergency lighting using traditional technology is rare and tends not to be a feasible option for end users.

In contrast, LED luminaires require only a fraction of the power; for example a 400W SON Floodlight can be replaced by a 136W SPARTAN LED equivalent. This saving on power means an emergency backup battery does not need to be as powerful, allowing the use of a smaller, lighter battery which keeps the size and weight of the luminaire to a minimum. This also helps to reduce the cost of the luminaire, making the unit more affordable.


Even if the size and weight of a traditional emergency unit isn’t a problem, or the cost not a barrier, the functionality of the units still poses problems. A high power draw means that under emergency conditions the units can only provide output for a fraction of the time compared to a superior LED alternative. A SPARTAN LED Floodlight can provide 50% light output for up to 2 hours.

LED luminaires also allow an instant restrike when mains power is lost, ensuring there is absolutely no blackout when the emergency battery kicks in. In comparison, traditional technology may require up to 15 minutes to fully strike when power is lost; a long wait under emergency conditions and in a hazardous environment.

Other Benefits of Emergency LED Lighting

Emergency LED luminaires also provide greater flexibility than traditional Ex lights. Each application is likely to have different requirements for its emergency lighting; some may prioritise light output under emergency conditions, while others May require an extended running time by using a lower output level. SPARTAN luminaires can be programmed with different light output under emergency conditions in order to provide the best balance between light output and running time, and the most suitable solution for each application.

SPARTAN luminaires also provide flexibility through their modular design. On-site lighting requirements will not always remain the same; for example, standard luminaires may need to be replaced with an emergency fitting. Thanks to SPARTANs modular design, a standard variant can be upgrade to emergency at any time with an additional battery backup module, meaning a unit can simply be upgraded rather than replaced, saving time and cost.

SPARTAN is a full range of Hazardous Area luminaires, including Flood, Linear, Bulkhead and Transportable. All products are available as emergency variants, with a selectable light output and instant restrike, and come with an industry leading 5 year warranty.

Explore the SPARTAN range here 

Require more information? Phone us on +44 (0) 1670 520055 or email us on sales@raytecled.com.

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