Working with Ultraviolet Radiation

Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength between 100nm (nanometers) and 400nm. This is less than the wavelength of visible light, so you cannot see UV radiation. There are 3 types, each of different wavebands: UV-A (400-315nm), UV-B (280-315nm) and UV-C (100-280nm).

UV radiation is used for a range of applications in the university, such as germicidal sterilisation (UV-C), fluorescence and photolithography (all wavelengths).

Starting Work

Before you start work in which you could be exposed to UV radiation you should be aware of the hazards involved and the common-sense guidelines for avoiding such hazards. Depending on the level of risk that your work presents, you may also need to consider the university's safety protocols.


The risk presented by UV rays depends on their wavelength and the beam intensity, with UV-B and –C radiation being more hazardous. With this in mind, UV radiation is distinguished by two categories: uncontrolled, which is considered safe, and controlled, which poses certain risks and is therefore subject to safety protocols.

Uncontrolled UV radiation

Uncontrolled UV radiation is considered inherently safe and therefore does not invoke any particular safety controls – you can ensure your safety just by using common sense.

Any person (including undergraduates) can work with uncontrolled UV radiation providing that they know how to use their equipment properly. There is no need to for a local induction or special training.

Generally speaking, equipment that emits only UV-A wavelengths is classed as uncontrolled, unless the intensity of the radiation is particularly high. For example, the Chemistry Department's HIRAC uses only UV-A radiation but produces it at such a high intensity that even a small amount of exposure could damage your eyes or skin.

Controlled UV radiation

Controlled UV radiation (i.e. UV-B, UV-C, and very intense UV-A radiation) is strong enough to damage the skin and eyes, while prolonged exposure could lead to health effects including accelerated skin aging, eye cataracts and, in some circumstances, skin cancers. Consequently, those who will come into contact with controlled UV radiation should be aware of the risks involved and consider the safety procedures for avoiding such risks. This information will be covered in the following pages.

Further information

Uncontrolled UV radiation