Under the Health & Safety at Work Act 1974 an employer has a duty to ensure the health & safety of employees. The Act includes a duty to provide lighting to ensure that work can be done safely and that employees health or eyesight are not jeopardised.
The provisions contained in the Management of Safety at Work regulations, especially regulation 3 'risk assessment', are also relevant.
Regulation No.8 of the Workplace Regualtions 1992 states that employers must ensure that:
Guide to required light levels
The amount of light required depends on the type of work being done, but the lisr below gives an indication of the amount of light required for the different kinds of work:
Movement of people (storage area and plant room) 150-250 Lux
No perception of detail (construction, loading bays) 300-500 Lux
Limited perception of detail (factories, kitchens) 500-750 Lux
Demanding work (inspection, welding, machinery) 750-1000 Lux
Repetitive work (electronics, textile production) 1000-1500 Lux
Accurate detail (technical offices) 1500-3000 Lux
Precision detail (jewellers and goldsmiths) 3000+ Lux
Typical Outdoor Light Levels
Interior levels are much lower than outdoor natural light. Some typical light levels are:
Very bright summer day 100,000 Lux
Full daylight 10,000 Lux
Overcast summer day 1,000 Lux
Very Dark Day 100 Lux
Twilight 10 Lux
Deep Twilight 1 Lux
Full Moon <1 Lux
Light can be measured in many ways. Lux and Footcandles are the two most popular measurements chosen by industry. The ‘lux’ range is a European standard, and ‘Footcandles’ are a US scale.
Lux (Lux) is a unit of illumination of one square metre, which is one metre away from a uniform light source.
Footcandle (FC) is a unit of illumination of one square foot, which is one foot away from a uniform light source.
1 Lux + 0.0929FC 1 FC = 10.76 Lux