Fluorescent light tubes and high intensity discharge [HID] lamps contain mercury, which is a Resource Conservation and Recovery Act (RCRA) characteristic hazardous waste (D009).  The disposal of mercury containing wastes is regulated by the Environmental Protection Agency (EPA) in Title 40 Code of Federal Regulations (40CR), Part 261, "Identification and Listing of Hazardous Waste."  Title 40 CDR 261 defines four characteristics, which can make a waste hazardous: ignitability, corrosivity, reactivity and toxicity.  Mercury has the characteristics of toxicity.  This means if a representative sample of waste containing mercury is analyzed using the EPA’s Toxicity Characteristic Leaching Procedure (TCLP) and the mercury content of the leach ate is equal to or exceeds 0.2mg/L; the waste is classified as hazardous.