DTH Portable Appliance Testing Services are here to ensure that all your portable appliances are safe for use in conjunction with Regulation 4 (2) of the Electricity at Work Act 1989. We also offer a day or night service including out of hours contracts. Our qualified engineers who are all City and guilds qualified and use the most advanced PAT testing equipment available all testing will be completed accurately and safely causing minimal disruption to your staff, business and clients. The Electricity At Work Regulation focuses on the "Duty of Care" in relation to any machinery connected to the electricity supply via a removable plug.