The US EPA suggests the following testing procedures in their August 2022 document titled "Guidance for Developing and Maintaining a Service Line Inventory". The service line may be visible where it comes into the building, such as in the basement where it connects to the water meter and/or premise plumbing. After locating the service line, the pipe can be visually inspected. A common approach to determine pipe material is a scratch and magnet test. If the pipe is a silver metallic color, carefully scratch the pipe with a key or coin. It is important to not use a sharp object that could puncture the pipe. If the pipe is soft, scratches easily, and reveals a shiny silver color, the pipe is likely lead. A magnet can be used to confirm the material since magnets will only react to steel and will not stick to lead (Hensley et al., 2021). Wear gloves when performing a scratch test and clean up any debris when the test is complete.
