Interstate Technology Regulatory Council (ITRC) has released an updated Technical and Regulatory Guidance as an online resource. This update includes a broad expansion in the discussion of PFAS in several contexts, including naming conventions, bioaccumulation, treatment technologies and sampling and analytical methods. Other sections of the document have also been selected for additional content, including information in regarding the health effects of PFAS, the mechanisms of fate and transport of PFAS, and the change to fluorine free firefighting foams. The free resource is available here.