OPINION
Bad lighting is still bad lighting The more things change, the more they stay the same. Contractors ruined interiors with Cat 2 luminaires 30 years ago and they’re doing it again with LED panels, says lighting consultant David Tilley The result of this race to have the best lumen/Watt LED panel is spaces that are over illuminated, have unacceptable glare and deliver poor contrast and ambiance. Office retrofit projects can have 30 to 50 per cent more LED panels than required to achieve an acceptable lux level. There are a few reasons for this: • The original schemes were often designed to deliver 500 lux and included maintenance factors • Display Screen technology was still being developed. • The Cat 2 luminaire required relatively high numbers to achieve the required lux level. The result of the race to have the best lumen/Watt LED panel is spaces that are over illuminated, have unacceptable glare and deliver poor contrast and ambiance. Pic: Unsplash
In the UK, the Health & Safety Display Screen Equipment Regulations of 1992 saw the development of Cat 2 louvres. For wholesalers and contractors it was a sales opportunity that was not to be missed.
But these installations often resulted in the following:
While the Cat 2 Louvre was developed with the best intensions, it was installed without thought to the space and those working within the space.
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Over illumination for the application
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Uncontrolled glare
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Higher-than-necessary energy consumption
The cut-off angle that provided the control of glare, on the display screen, also resulted in flat and dull work spaces. Retrofit schemes gave little or no thought to the location of display screens or the various activities within the space.
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Increased potential for failures
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Increased cost of installation
Lighting standards were introduced to focus on the space, as a whole, which improved the working environment. A decade later, has history not repeated itself? With its lower energy consumption than a T5 or T8 fluorescent luminaire and its simplicity when retrofitting, the LED panel has become a game changer for the commercial lighting sector. But has the LED panel resulted in more poorly illuminated spaces than the Cat 2 luminaire? The answer is YES. While the CAT 2 luminaire was generally confined to commercial office spaces, the LED panel has become the contractor’s choice for numerous retrofit projects. There are very few sectors where you will not find an LED panel installed as a retrofit solution. The luminaire development plan of manufacturers was to continually improve the lumen output of the LED panel with little or no thought to the retrofit market which represents a significant percentage of LED panel sales. 52
Without a considered lighting design, clients and contractors simply compared the 72W (4 x 18W) energy consumption of a fluorescent luminaire, without gear losses, to a 30W or 36W LED panel and saw a 50 per cent energy saving. So they moved en masse to the new panels.
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The contractor will of course argue that point-for-point installation is the most cost-effective solution for a retrofit project purely based on not having to undertake a lighting design or a basic lighting review process. If a retrofit project can be completed with 30 to 50 per cent fewer LED panels the additional energy saving will be significant and often all that is required to complete the project is a few ceiling tiles. Even worse is the installation of LED panels in retail spaces without any thought to the requirements of the staff and, more importantly, the customers. Stores look flat and clinical, merchandise isn’t highlighted and customer navigation around the store is impaired. Clients need to understand that lighting is an integral element of the sales process. Leaving a retrofit project to a contractor with no guidance is a receipt for disaster. The good news is that lighting manufacturers are providing LED panels with lower lumen outputs and improved glare control. The bad news? Contractors will still look for the cheapest option. ■