'll just add to that , Pat testers charge per test, as has been said above, and therefore have a financial incentive to bend the regulations and claim that they apply to as many things as possible. There are no statistics produced to show that PAT testing ever avoided a single workplace accident, Which are and have been at an extremely low level for many years now. when first introduced, my local jobcentre was using the then current "Back to work grant" to buy a pat tester and a 2 day course for the long term unemployed to get them off their books! Add to that that most of the companies set up to milk this cash cow folded within months of inception, and you begin to get a handle on how interested parties become lobbyists for the introduction of new legislation to in order to "curb the rising tide of workplace electrical accidents" and thus create a marketplace for their equipment or service. They then ensure that the specifications are changed every couple of years in order that all the operators have to purchase new equipment if they wish to continue testing, and thus the "industry" implodes, and the lobbyists look to creating more money out of milking some sector that they can foist more unneccasary legislation onto. This is why it is a bad idea to allow equipment manufacturers to have a hand in drafting IET regs, their only motive is profit, not safety!