Application of treated biosolids to land can be helpful as a crop nutrient and soil conditioner but may pose the risk of releasing pathogens into the environment if proper disinfection and use criteria are not met. Among these organisms are Salmonella, which are pathogenic enteric bacteria that can cause salmonellosis in animals and humans, if concentrations able to give rise to infections are present. The density of Salmonella in Class A biosolids for unrestricted use is to be less than three most probable number (MPN) per four grams of total solids (dry weight basis) at the time the biosolids are used or disposed. Method 1682 is a performance-based method for detecting Salmonella in biosolids. Method 1682 requires calculation of the MPN via enrichment, with selection and biochemical confirmation for determination of Salmonella. The enrichment step utilizes tryptic soy broth (TSB). After incubation, TSB is spotted onto selective modified semisolid Rappaport-Vassiliadis (MSRV) medium. Presumptively identified colonies are isolated on xylose-lysine desoxycholate agar (XLD). Biochemical confirmation includes lysine-iron agar (LIA), triple sugar iron agar (TSI), and urea broth, followed by serological typing using polyvalent O antisera. Calculations for concentration are based on dry weight.