Interpretation of the calculation result

1. Scrutinise carefully

  • To prevent glare – check the luminance conditions in the room.

2. Maintenance factor

  • Has the maintenance factor been adapted to a maintenance plan for the lighting installation?

    NOTE! The maintenance factor affects the lighting system’s energy consumption.

3. Calculation conditions

  • Have the conditions for the lighting calculations been checked?
  • Has the size of the working area and immediate surroundings been established?
  • Has the calculation area for the peripheral area been defined?
  • Have the room surfaces’ reflectance values been checked?
  • Has the luminaire’s average luminance been checked in rooms used for monitor work?

4. Uniformity demands

  • When calculating the illuminance uniformity i.e. the ratio between the minimum value and the average value in the working area and the immediate surroundings and for the peripheral surroundings, it is important that the distance between the calculation points is documented. For normal working areas in offices a maximum spacing of 0.2–0.3 m between calculation points applies.

5. Significance of the gradient

  • Excessively large differences in illuminances and luminances within the normal field of view can cause visual difficulties. Therefore, the scales for changes in illuminances and luminances indicated in standard EN 12464-1 should be used.

6. Limit values of luminaire luminance for working at a monitor

  • Verify that the luminaire luminance does not exceed the limit value according to EN 12464-1.

7. UGR-glare index

  • Check, where appropriate, that the system’s average glare index conforms to the value stated in the standard.

8. Energy efficiency

  • Are the energy requirements of the Part L building regulations and EN 12464-1 being complied with?