"The Resource Centre For Hazardous Area Professionals"

Social Media

Modular vs Sealed for life: Maintaining Ex Lighting Part 1

Print PDF
User Rating: / 0

hes 06 19 3When sourcing lighting to install in hazardous areas there are various things to consider. These include cost, performance and reputation of the manufacturer, but how much thought do end users give to ease of maintenance? For many, the answer to this question is probably, ‘not enough’.
By understanding the terms ‘modular’ and ‘sealed for life’ LED Ex luminaires, we can compare how the design and certification of these different approaches impacts the ease of maintenance.

In hazardous areas, maintenance of lighting is key as it ensure the luminaires are compliant and are operating at their optimum. However, carrying out the maintenance can be challenging and costly (both from a financial and environmental perspective). Choosing an LED solution will help to ensure maintenance is kept to a minimum, but the challenging nature of hazardous area applications means routine maintenance checks are essential, and as with any other electrical product, unplanned maintenance is still a possibility. Ensuring maintenance of the luminaire can be carried out as quickly and as easily as possible is vital.

But, how do you know whether a luminaire is easy to maintain or not? Simply put, Ex luminaires can be categorised in two ways:

Sealed for Life Luminaires – Many Ex lighting solutions are factory sealed (or encapsulated), primarily as a method of protection (as part of the luminaires hazardous area certification). Once sealed, the luminaire cannot be opened up and internal components cannot be accessed, i.e. ‘sealed for life’. From a certification perspective, this design is generally perceived as being a more straightforward method of achieving Ex approval but does have its limitations. Because the factory seal is such a critical part the luminaires hazardous area rating, it cannot be opened without invalidating the certification. Doing so would render the unit unsuitable for use in hazardous areas and could present an explosion risk. As a result, maintenance of a sealed for life luminaire is very limited.

Modular Luminaires – In contrast, ‘modular’ luminaires are specifically designed in a way which allows them to be opened up and accessed for maintenance, without invalidating certification. This is mainly because the luminaire does not rely on being factory sealed to achieve its hazardous area rating. While encapsulation may still form a part of the certification, this is likely to be at a component level (such as encapsulated drivers), rather than the entire luminaire. Without this restriction, maintenance becomes much easier and components can be changed or inspected without invalidating the luminaire’s certification.

By understanding these differences, you can choose a lighting solution more carefully. Maintenance is inevitable with any luminaire, LED or otherwise, so having the ability to fix any problems on site is a huge advantage.

To find out how our luminaires can benefit your project, call us on +44 (0) 1670 520 055, or email Raytec Global at This e-mail address is being protected from spambots. You need JavaScript enabled to view it  
You can also explore our modular SPARTAN range here: