Dark work environment in plastic factory
Factory workers are checking the production line.

Lighting at work

Good lighting is important for the performance of your work, and too little light may cause health problems

In the photo above, you can see that this workplace does not have enough lighting. The factory produces plastic sheets (tarpaulin) from recycled plastic, and the workers are checking the production line. There is a high risk for accidents here, since it is difficult to see the moving parts of the machine Also, it is difficult to see any possible production errors in this dim light. This simple real-life example underlines that good lighting in the workplace is important.

What is light?

Light is electromagnetic radiation from a specific part of the electromagnetic spectrum. When we use the word “light”, we usually mean only visible light, that is, radiation that is visible to the human eye. The light level is often called illuminance. In the metric SI system, illuminance is measured in lux. One lux is one lumen per square meter. A dinner candle, for example, generates about 12 lumen, while a typical 60-watt light bulb can generate 840 lumen. The light level (illuminance) outdoors is approximately 10 000 lux on a clear day. Light can be measured with a light meter, also called lux meter. Such instruments are generally not expensive and are relatively easy to use.

Sufficient lighting in the workplace - recommendations

The level of lighting you need at work depends on the task you are performing. There are no clear guidelines for optimal lighting level, but several institutions and countries have developed suggestions. Some examples of light level recommendations are given in the table below (Health and Safety Executive, United Kingdom).

Work activity Average illuminance needed
Movement of people, machines and vehicles on construction sites 50 lux
Work requiring limited perception of details, for instance in kitchens 100 lux
Work requiring perception of details in factories, offices, shops 200 lux
Work requiring perception of fine details in electronic factories, textile production, normal office work 500 lux

Light and health

Inappropriate lighting may cause several health problems, as if may cause strain of eye muscles. If the workers have to use the eye muscles more than normal, it may also lead to strain in other muscles, for instance in the neck. Insufficient lighting may cause:

  • Headache
  • Muscle pain in the neck
  • Fatigue

There may be increased rates of accidents and injuries occurring where the light is insufficient. Lack of light is clearly a safety hazard. In addition, work productivity can be reduced when the workers do not see properly. One should also be aware of differences in individual need, regarding light. Age is one important factor. Elderly people need more light than younger ones. Some people need glasses! Employers should consider checking the vision their workers. Providing corrective eyeglasses where necessary can make wonderful improvements for some workers; reducing stress and headache.

Improving the light at work

There are many different lamp types. Choosing the best type of lamps for a workplace can be challenging. However, there are also other factors to consider in addition to the lamps themselves, such as:

  • Natural light is most often the best. Having enough windows can be very useful.
  • Keeping light sources and windows clean is important to ensure that sufficient light is obtained.
  • The location of the light source is important; glare can make light unpleasant and disturb the vision.

More information

ILO has provided a report named: Physical hazards – Indoor workplace lighting. This report gives several good ideas for how to improve light at work. You may find the report as a pdf- file and this can be useful reading.

In addition, HSE, UK has made a free-to-download book called ‘Lighting at work’.

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This article is from the free online course:

Occupational Health in Developing Countries

University of Bergen