Volume IV of the World Health Origination (WHO) Guidelines for the safe use of wastewater, excreta and greywater addresses the reuse of all types of greywater (including kitchen greywater); however, it Furosemide does not specifically address greywater reuse for dishwashing, focusing instead on reuse in agriculture ( WHO, 2006). The WHO guidelines are based on a microbial risk assessment approach, recommending a maximum health burden that does not exceed 10− 4 to 10− 6 DALYs per person per year. NSF International (NSF) and the American National Standards Institute (ANSI) recently published international guidelines for water reuse. The NSF/ANSI Standard 350: On-site Residential and Commercial Water Reuse Treatment Systems and the NSF/ANSI Standard 350-1: On-site Residential and Commercial Greywater Treatment Systems for Subsurface Discharge provide guidance on water quality standards ( Table 2), methods of evaluation, product specifications, and product literature for greywater treatment systems. In addition to producing these guidelines, NSF and ANSI also certify treatment systems. While NSF/ANSI certification does not necessarily satisfy regulations in all countries or states, bark does provide a consistent standard that is recognized internationally.