The unit is in no way intended for the use of prevention of skin cancers or as a benchmark for advised Vitamin D intake.
However, as the timing system will go some way towards these issues, I would like to follow out a little research in just how long it would take for someone to achieve their RDA of Vitamin D through natural sunlight.
There have been a huge number of studies into the correlation of UVA and UVB radiation and skin cancers; however, it is also evident that a short amount of time in the sun each day can be beneficial to reaching our daily intake of Vitamin D and also for general well being.
It is widely accepted that the time needed to expose your skin to the sun in order to gain enough Vitamin D, is much less than the time you would spend sunbathing to produce a tan or suffer sunburn.
Because the device would only operate during the week; when people are typically working, it would only be used for these short breaks you might or might not take as the case may be.
Because the device would only operate during the week; when people are typically working, it would only be used for these short breaks you might or might not take as the case may be.
According to The British Association of Dermatologists, '...the range of vitamin D intakes required to ensure maintenance of wintertime vitamin D status of 20 to 40 year old adults, considering a variety of sun exposure preferences, is between 7.2 and 41.1 micrograms/day.'
This figure seems to equate to around 10-15 minutes in the noonday sun. See here and here for suggestions.
If that period of time is the maximum one should spend in the sun without protection whilst the sun is at its strongest, then during cloudier days, that time would supposedly increase.
As this project is born of personal interest without any view to market, I will fabricate a system based on the little information that I have. In an ideal situation, this project could warrant further research, professional advice and rigorous testing.
Presently however, I hope to simply build a rough working prototype, based very loosely on general information that I gather together regarding the health implications of UV.
In terms of translating that 10-15 minute daily recommendation into the system, each LED could represent 5 minutes. Therefore, in the strongest rays, at the hottest period in the day - between 11am-3pm, only 3 LED's would illuminate. If it were cloudier or outside of those hours, more LED's would activate relative to the UV levels.
The prototype will be suited to my personal situation - being located in London, being fair skinned with light hair. This would vary if you were in a country with warmer climes and had darker skin, which would increase time for the skin to burn and absorb Vitamin D.














