UGR19 lighting is a headache ?
No, UGR19 isn’t a headache but the guidelines and the working out and the procurement of it is. The UGR glare index runs from 13 to 28, luminaires with a UGR of 19 or less is the guideline for office spaces set down by the Society of Light and Lighting’s code LG07/15 Lighting Guide 07: Offices – LG7. Which in turn meet The European Standard,
Specifiers are increasingly looking to meet their compliance challenges by specifying UGR19 compliant fittings with contractors. This leads to the increasingly common question “Is that fitting URG compliant?” strictly speaking the answer is No, manufacturers can only supply fittings that support the UGR19 guideline as the calculation must take into account the physical occupancy of the space that is lit.
So UGR19 is not a property of the luminaire?
That’s right it is not, So what do you do? The standard measure for a UGR<19 fitting is what the luminaire would have in a room with the dimensions of 4H/8H and degrees of reflectance of 20% for the floor, 50% for the walls and 70% for the ceiling. Most office spaces are generally not the size of a shipping container, (Unless it is an edgy office in Shoreditch and workers really are sitting in shipping containers). In real world situations, the UGR value could be lower or even higher. Proper compliance only comes when measured within the space the UGR19 luminaire is to be fitted.
