This is a listing of products approved for use with standard, alternate, and experimental sewage disposal systems that are in addition to the products listed in Rules and Regulations Pertaining to Sewage Disposal Systems, Designated Representatives, and Installers. All products on this list must be installed according to the procedures and directions provided by the manufacturer. Failure to do this voids this approval. The telephone numbers are, in most cases, for the manufacturer of the product. To find a local distributor, you may try the number listed or the local environmental health specialist.