UGR is a calculation method that helps lighting designers create schemes to avoid the discomfort of misplaced light .
L= The luminance value of the luminaire
Lb= The value of the background luminance
ω= The solid angle of the luminaire that is seen by the viewer
p= The Guth Index. Based on the likelihood of glare, also known as Visual Comfort Probability
Σ= Shows that the equation (shown above) includes all the fittings located within the area.
WESTDEER UGR<19 Led Panel Lights
The references made to UGR are held within lighting application guides such as Light Guide 7, published by The Chartered Institution of Building Services Engineers (CIBSE), which recommends that office environments do not exceed a UGR of 19. At this point it must be made clear that UGR is a function of the installation environment and not the individual luminaire. To correctly assess the level of glare a professional lighting design must be carried out. Note: UGR is not a product criteria. No product based standards apply any limits.
Original Article : https://integral-led.com/education/what-is-ugr