What happens if cross connection control devices are not in working order?

The correct choice indicates a critical issue related to public health and safety. When cross connection control devices, such as backflow preventers, are not functioning properly, they fail to provide the necessary barrier against potential contaminants. This malfunction can lead to a situation where harmful substances from non-potable sources might siphon back into the potable water system, resulting in contamination.

The presence of these devices is essential for maintaining the integrity of the drinking water supply. They create a one-way flow, which is crucial for preventing any undesirable materials from entering the clean water system. Without properly working cross connection control devices, the risk of waterborne diseases and health hazards increases significantly, which is why adherence to maintenance and operational checks for these devices is vital for protecting public health.

Understanding the implications of this choice highlights the importance of regular inspections and maintenance of all cross connection control devices to ensure that they are operational and effectively preventing contamination risks.