TCLP is one of the Federal EPA test methods that are used to characterize waste as either hazardous or non-hazardous for the purpose of disposal. TCLP is an acronym for Toxicity Characteristic Leaching Procedure. It is performed by environmental testing labs. The TCLP test does not measure total mercury content; rather, it measures the potential for mercury to seep or "leach" into groundwater if a waste is landfill disposed.

In the TCLP test, lamps are crushed into small pieces and mixed with an acidic solution. The acidic solution is then filtered from the lamp pieces. If less than 0.2 mg of mercury are found per liter of acidic test solution, the waste is characterized as non-hazardous waste under federal law.

In most states, here are no special disposal requirements for non-hazardous waste lamps.*