While working on artificial lighting simulations for an office building with an open office layout, it is found that in some areas the light exceeds the 300 lux level recommended for commercial offices. However, the average lux level for the whole space is around 200 lux. Can you kindly confirm whether Criterion 13, GRIHA Version 3 requires us to achieve the 300 lux for the whole space as an average or under the light fixtures where the workstations would be placed?
In Criterion 13 (GRIHA Version 03), the average lux levels in each working plane/zone must adhere to the NBC 2005 levels. So the office desks should have at least 300 lux level as average and adjoining public area may have 200 lux level as average. Each activity area must meet their respective NBC 2005 lux level and the analysis and documentation will have to be done in that manner. Otherwise, in case of lighting level calculation being done for the entire space, the average lux level must satisfy the space with the highest threshold requirement.