1. UVI Sensor A device for real-time measurements of UV Index Dr. Alan Bates Department of Mathematics, Natural Science and Computer Science John Cabot University Via della Lungara 233 00165 Rome, Italy

2. Why measure UVI?  Skin cancers rates are increasing significantly since 1970s particularly among fair-skinned people (+4% per year in the US)  Skin aging is accelerated with increased exposure to UV  Strong reflection from surfaces (sand, water and snow) can cause damage to the eyelids and eyeball tissues  Level of awareness of the potential risks of UV exposure is generally low

3. WHO Protection Scheme Recommended sun protection scheme

4. Calculating UVI  E λ is the solar spectral irradiance (measure of solar spectrum transmitted through atmosphere) – varies by day, season and latitude. Can be measured with a spectrometer  S er ( λ ) is the erythema reference action spectrum for human fair skin. k er is a constant equal to 40 m 2 /W  UVA (315–400 nm); UVB (280–315 nm); UVC (100– 280 nm)

5. Existing UV sensors ML8511 (Lapis Semiconductor)  The sensor outputs an analog voltage that is linearly related to the overall UV intensity, 280-390 nm  The output is a summation of contributions from all UV wavelengths - a type of average value  Advantages: fast real-time measurements; small in size; requires little power  Disadvantage: approximate value of UVI

6. Si1132 (Silicon Labs)  Sensor measures visible and IR intensities  Algorithm calculates UV index  Advantages: fast real-time measurements; small in size; requires little power  Disadvantage: +/- 1 difference compared to actual UV index

7. The Idea! Accurate calibration under various atmospheric conditions/UVI values is re  Notice for both sensors the UVI values are approximate  We need a fast and accurate measurement of the UVI  Utilize UV spectrometer to measure actual real-time UVI values under various conditions (UV spectrometers are expensive)  Simultaneously record output from the ML8511 with the Arduino microcontroller  Write algorithm to relate ML8511 output to actual UVI value in real-time under a wide range of atmospheric conditions

8. Displaying UVI UVI values on a LCD display with WHO recommendations Light with colors corresponding to WHO recommendations Sound alarm if UV Index is above a certain value, for example index 8 or above Online internet site

9. 2 Sensor Types  Wall-mounted for public display in schools, outdoor workplaces and public institutions involving outdoor work to communicate UV Index  Wearable to fit on clothing to measure personal UV Index

10. UVI Network Connect  Sensor connected to internet to stream live data to online map  Updated every minute  Accurate measurement of UV Index across country, regions and provinces Real-time measurement

11. Grazie!