Short and intensive UV radiation may result in temporary snow blindness (photokeratitis).

But even very low UV levels are having a long-term accumulating effect on the lens of the eye, resulting in cataract or clouding of the lens.

So a home-designed UV eraser must make sure that the UV light source may never be on in a situation where the light may leak out from the eraser.

The easiest way to get a safe UV eraser is of course to buy a real one.

But an even easier solution is to skip ancient technologies that makes use of UV erasers - EEPROM solutions are so much nicer to work with.