The UV 4 Click Board™ is a powerful Ultra Violet (UV) sensing device and Ambient Light Sensor (ALS) Click Board™, featuring a sensor with a very wide dynamic range of detectable light intensity, across two ADC range settings. The UV diodes are matched to CIE erythema action spectrum, allowing a very accurate calculation of the UV index. The UV Index is standardized by the World Health Organization and it represents the strength of sunburn-producing (UV) radiation.