US DEF suppliers, Colonial Chemicals Co., Terra Environmental Technologies and Yara have been awarded licenses by the American Petroleum Institute (API) under its new Diesel Exhaust Fluid Certification Program. Colonial Chemical, based in New Jersey, was the first to be awarded the license which recognises that the certified company meets the strict ISO quality standards for DEF. The API then awarded a licenses to Terra Environmental Technologies, and most recently Yara. The new API license scheme has been designed to assure high quality of DEF sold in the US market.























