This document serves as a practical guide for anyone responsible for supporting safe household water treatment. It offers direction on how to organize and carry out sanitary inspections that identify contamination risks throughout a household water system. It is designed to help implementers, WASH officers, community health promoters, and regulators understand how to select inspection forms, engage effectively with households, and collect meaningful information that supports safer water practices. It is useful in routine monitoring, disaster response, technical follow-up, and any situation where organizations need to assess water safety, support households, and improve the reliability of household water treatment technologies.