Lighting design

The maintenance factor required for determining initial illuminance which describes the installation’s operating behaviour must be agreed upon by designer and operator of the lighting installation according to EN 12464-1. Where this is not possible, the following reference maintenance factors are to be used for planning:

• 0,8 for short periods of use or low degrees of soiling in relation to cleanliness requirements in healthcare rooms, or

• 0,67 for normal periods of use or high degrees of soiling in relation to cleanliness requirements in healthcare rooms.

These values assume a higher degree of cleanliness and soiling prevention in healthcare rooms compared to most other work places. This excludes rooms, e.g. for domestic engineering uses, where a higher degree of soiling may be the case.

The numerical requirements for lighting are summarised in table to table.

According to EN 12464-1, the wall surfaces (primary surfaces) in hospitals must be illuminated with at least 75 lx maintained illuminance and the ceiling must feature a maintained value of at least 50 lx (uniformity at least 0,10 for both).