Luminance Reflectance Value Calculator (LRV)

LRV Calculator (Bowman-Sapolinski)

This calculator may be used to calculate the Luminance Reflectance Value (LRV) between two elements. LRV Requirements vary for different building elements and types of building elements.

The Bowman-Sapolinski Equation is used to calculate the LRV readings, in line with Part B4 of AS 1428.1 (2009) and Part E3 / E5 of AS/NZ 1428.4.1 (2009).

The equation is of the form C = 125 (Y2 − Y1)/(Y1 + Y2 + 25). C is equal to the calculated contrast, and Y1 and Y2 refer to the luminous reflectance values (LRV) of the two surfaces to be calculated. Y1 is to be darker than or equal to Y2.