A UV exposure dosimetry system includes at least one UV sensor that measures the UV irradiance intensity. The system can generate extrapolated UV intensity data based on measured UV intensity data to correct unreliable UV measurement due to inconsistent irradiation of UV light. The system integrates the extrapolated UV intensity data over time to calculate real-time UV dosage and vitamin D production by taking into account factors including UV sensor location, body surface area, clothing coverage, and sunscreen usage. Based on the measurement, the system can predict the time remaining to skin burn and the time remaining to reach daily goal of vitamin D production. The system is also adapted to measure sun exposure time based on the corrected UV intensity over a period of time. The UV dosimetry system supports multi-user control through an advanced and user friendly input and output interface.
