A technical description of the design of a new type of radiation monitors is given. The key point in the design is the low power consumption inferior to 17 mW in radiation sensing mode and inferior to 0.3 mW in standby mode. The radiation monitors can operate without any external power or signal cabling and measure and store radiation data for a maximum period of 800 days. To read the radiation data, a standard PC can be connected via a USB interface to the device at any time. Only a few seconds are required to read out a single monitor. This makes it possible to survey a large network of monitoring devices in a short period of time, for example during a stop of the accelerator
