I just googled...but check it out: http://www.completecarpetcare.com/EPA_recommended_cleaning_schedule.html http://carpetmanclean.com/page/13y59/Free_Information/EPA_Guidelines.html http://quality-carpetcare.com/epa-guideline.htm Here is a PDF from 2004 guideline from the gov...: http://www.epa.sa.gov.au/pdfs/guide_carpet.pdf