PAT testing (aka Portable Appliance Testing, or electrical equipment testing) is a safety procedure carried out on a periodic basis, on electrical equipment used in workplaces, to make sure it is safe to continue using.
The purpose of doing PAT regularly, is to make sure that users of equipment, customers, the general public, employees, tenants, students, pupils, children, etc are not going to be at risk of injury from them.
In the UK, under Health and Safety at Work Regulations, the Electricity at Work Regulations (1989) makes your obligations quite clear – “All systems shall at all times be of such construction as to prevent, so far as reasonably practical, such danger“. This means that you need to make sure that your electrical systems (wiring installation and appliances that plug into it) are always safe to use. So, businesses and other owners/managers of work places like schools, hotels, doctors surgeries, hair salons, etc. need to observe regular testing protocols to minimise the risk.
It is considered best practice to Pat test portable electrical equipment (in most workplaces) once a year; and in some higher risk locations, more often than this.
Although there is no legal requirement to do annual PAT testing, it is considered best practice, and tends to be the most acceptable process, especially if you don’t have risk assessments in place.
Also, keep in mind, if you allow other businesses to operate on your premises (like mobile disco’s in hotels), their equipment needs to be PAT tested too – and to protect your own policies you will need to check this.