The U.S. Occupational Safety and Health Administration (OSHA) and U.S. EPA regulate TDIs.
OSHA has set a permissible exposure limit (PEL) for 2,4-TDI and the National Institute for Occupational Safety and Health (NIOSH) has set recommend exposure levels for 2,6-TDI and TDI, mixed isomers (see Table 3).
The U.S. EPA regulates TDIs under the authority of the following three environmental statutes:
- Clean Air Act: 2,4-TDI and 2,6-TDI are "regulated toxic, explosive, or flammable substances."
- Comprehensive Environmental Responsibility, Compensation and Liability Act (popularly known as "Superfund"): 2,4-TDI and 2,6-TDI are regulated as both an "extremely hazardous substance" and a "hazardous substance," whereas TDI (mixed isomers) is only regulated as a "hazardous substance."
- Emergency Planning and Community Right-to-Know Act, TRI program: all large quantity users of 2,4-TDI, 2,6-TDI, and TDI (mixed isomers) must submit data on environmental releases and off-site transfers.
The data in this section are from the following sources: EDF, 1999; and New Jersey Department of Health and Senior Services, 1996 (see endnote #1 for full citations).