How to Light

How to Light: What is best practice for lighting high-level racking in warehouses?

This question was answered by the technical team at Tamlite.

Looking at ‘best practice’ in its broadest sense, there are a number of issues to be considered.

Light efficiency and energy management

An efficient lighting scheme will also deliver efficient energy management. To begin with, lighting is only required when people are present in the area; for the rest of the time, there is no need for lighting, and therefore no need to expend electrical energy.

1. Use presence detectors to ensure that energy is not being wasted. Many industrial sheds are built with rooflights, providing a level of natural light ingress. Artificial lighting need only supplement the free daylight entering the building. Dimmable lighting offers more energy saving by lighting only to the levels necessary.

Racklite is a continuous linear system suitable for warehouse or retail areas.

2. Use daylight sensors to control the amount of artificial light needed. The light distribution required for high-level racking is not the same as that needed in open-plan spaces. The ‘canyon’ effect means that the light distribution from the high-level fixtures should be ‘narrow-wide’, meaning that the light spreads along the length of the racking aisle (wide), but drops steeply downwards in the direction of the racking (narrow).

3. Use LED high-bay fixtures that are fitted with an optical system designed for racking aisles. It’s important to ensure that the light fixtures are located appropriately. Fixtures that are mounted on top of racking does not provide adequate illumination, wasting energy and reducing effective illumination. The most important aspect of optical system design is to ensure that the vertical surfaces of the racking are well illuminated. This is where the work is done and where visual detail needs to be identifiable.

4. Ensure that the lighting arrangement matches the footprint of the racking – or vice versa, if the lighting is already in place when the racking is built. This may seem obvious, but it’s not uncommon for lighting fixtures to be installed where it’s most convenient for the installer, rather than where the light needs to be for the operator. Make sure that there is proper coordination between trades.


Racklite offers high performance optics with narrow distribution, ideal for racking aisles.

Lighting for people

It’s also important to remember that we only provide illumination for people. Lighting quality is a significant factor in the success of an installation – and the efficiency of a business.

5. Ensure that the colour rendition of the LED sources is fit for purpose. Fixtures should provide at least CRI 80 for this purpose. It’s not just a case of providing illumination; it’s vital that the light meets the needs of those working among the racking. Colour accuracy is important when operatives need to visually recognise product code identification.

6. Use LED high-bay fixtures that are fitted with good-quality optical systems. Glare can also be a problem when working at high level. High-bay fixtures need to be fitted with good- quality optical systems to ensure that illumination levels can be met without jeopardising operatives’ ability to work, particularly when loading or unloading at high level. As discussed above, the quality of light on the vertical surface is a vital part of any racking illumination.

7. Ensure that only good quality LED high-bay fixtures are used, where LED flicker is minimised. Flicker can be a serious problem in racking aisles, where the confined space can exacerbate the effect of flickering LEDs. Flicker is not always immediately obvious. LEDs can flicker at a rate that may not be apparent to the viewer but can still have harmful effects on people’s health. Good-quality luminaire and electronics design overcomes this problem.

Further guidance on lighting industrial spaces

HSG38: Lighting at Work (HSE)
LG01: The Industrial Environment (free to Cibse/SL members)

To see other lighting questions answered by experts, click here.