Increasingly, Environmental Health Officers are notifying commercial customers that their UV systems need a fail to safe facility. This means that should the UV fail for any reason, for example a power outage, the UV system will cut off the flow of water and sound an alarm (audio and/or visual). In some cases, the EHO’s also recommend that telemetry is added to the system if equipment is installed in a remote area. The telemetry module on the UV sends a warning message to one or more mobile phones should a fault occur.