Using the technique of microbial risk assessment, concentration limitations of pathogenic microorganisms for various reclaimed water uses are studied. The concentration limitations are: Escherichia coli 70 MPN/L, Salmonella 0.5 CFU/L, Shigella 0.1 CFU/100L, Hepatitis A virus 0.001 PFU/100L, Rotavirus 1.2 x 10(-3) PFU/100L, Poliovirus 0.07 PFU/100L, Coxsackie 0.04 PFU/100L, Echovirus 0.05 PFU/100L, Cryptosporidium 0.1 oocysts/100 L, Giardia lamblia 0.03 cysts/100 L.