The University issues safety glasses only where their need has been established by risk assessment (e.g. to protect against reasonably foreseeable risks of eye injury). The safety glasses are supplied with prescription lenses, where necessary. Prescription safety glasses are a form of Personal Protective Equipment, or PPE, and in the hierarchy of risk control all items of PPE are considered to be the final line of defence. This is mainly because they protect only the user and do not take into account negation of the risk to others in the vicinity. However, because PPE is the “last resort” after other methods of protection have been considered, it is important that users wear it all of the time that they are exposed to the risk.