Brief guide to lighting levels
The CIBSE Code for Lighting is the comprehensive bible for all aspects of illumination – below is a brief guide on lighting levels.
Since 2002, the Committee for European Standardisation (CEN) has provided lighting recommendations, adopted by the British Standards Institution, with a range of British Standards (BS) specifying quantitative lighting requirements for many applications.
The CIBSE Code for Lighting has developed as a guide on how to interpret and implement the BS recommendations. It gives lighting requirements for areas and is replicated in BS EN 12464-1:2002 Light and lighting – Lighting of work places – Part 1: Indoor work places.
For reference, the lux is the international standard unit of illuminance and luminous emittance, According to Wikipedia, it measures luminous flux per unit area. It is equal to one lumen per square metre. In photometry, this is used as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface.
From this, the code provides detailed advisory information on lighting levels in a wide range of settings.
Effective Lighting Levels
Source: CIBSE Code for Lighting 2002. http://www.cibse.org/knowledge/cibse-lg/sll-code-for-lighting
In education, the need to illuminate learning spaces well is crucial for effective teaching and students’ well being. The table below outlines the best lighting levels in main areas.
Best Lighting Levels
The code provides excellent advice in commercial, leisure and domestic environments. Below are a selection of lighting levels for different areas.
According to The Lighting Guide 7 (2005), for offices the recommended design maintained illuminance over the task area in any room ranges from 300 to 500 lux.
For work like data retrieval or telesales, the lower end of this range should be used and for tasks involving writing or copy typing, 500 lux would be needed.
For activities that require intensive concentration such as proof reading or technical drawing, higher levels should be considered.
The Health and Safety Executive has set a minimum level for any permanently occupied area of 200 lux.
