Scales that use BIA technology use a low-frequency current that flows through the body to measure body composition. Read more about BIA technology here: How does TANITA measure body composition? If a scale with this technology is placed in a humid environment, such as a bathroom, basement or shed, the electrons may short-circuit and cause the scale to malfunction. The scales are not water/moisture resistant. Unfortunately, these defects also void the warranty. Read more about the warranty here: What is covered under warranty?