The Solar Sensor is a Davis Solar (6450) and UV (6490), which was part of the VP2 Plus package.
Located on the ISS unit in the garden, whilst not in an elevated position it gives a very accurate reading.

Using the Davis (6490) UVI sensor, we can measure the levels of UVA and UVB at ground level. This is important to understand the risks in exposure of our skin to sunlight.  UVA and UVB whilst giving us a healthy glow and a suntan also cause irreparable damage to our skin cells, causing aging, and sometimes leading to skin cancer.

Whilst our sensor is not a medical grade unit, it will give a general measure of the levels being experienced.

The UV Scale

The UV Scale was produced by the World Health Organisation, and uses a 16 point scale. This measurement gives us an indication of intensity, and also an indication of burn times depending on the skin type.

UVA (315-400 nm) and UVB (280-315 nm) are not absorbed by the earths atmosphere as much as the UVC wavelengths.

UK Solar Distribution Map - Source: NERC

Sun Position Graph by http://meteo.aerolugo.com