What is Visual Comfort Probability (VCP)
Visual comfort probability (VCP) is a term to measure the acceptability of discomfort glare in a lighting system. It is expressed as a ratio, represented as a percentage, of individuals who are likely to find the level of glare in a specific location and direction acceptable. VCP is closely related to the Discomfort Glare Rating (DGR).
The purpose of VCP is to assess the visual comfort experienced by individuals when viewing a lighting system. Discomfort glare refers to the interference with vision caused by excessive illumination, which can lead to discomfort and reduced visual performance. By calculating the percentage of users who are expected to find the glare level acceptable, VCP provides a quantitative measure of the overall visual comfort provided by a lighting scheme.