Each PT sample is one lyophilized standard, which can be analyzed for enterococci and/or fecal streptococci, MF or MPN in the range 201000 CFU/100 mL or MPN/100 mL. CRM also includes one blank sample. Use with EPA Methods 1106.1 and 1600, ASTM Methods D5259-92, D6503-99 and Standard Methods 9230B and 9230C and Enterolert Quantitray.