Radon daughter dosimeter

A portable radiation dosimeter unit for continuously measuring the working level exposure to radioactive particles in combination with a readout unit comprising:

• a detector head housing having a filter head and solid state surface barrier radiation detector contained therein;
• said head housing having an ambient air inlet and outlet adapted to allow air to flow through said filter head before contacting said radiation detector;
• an air pump to force ambient air into said head housing inlet to the filter and radiation detector;
• electronic circuitry connected to said radiation unit for receiving and processing charged electrons received therefrom by converting them to pulses whose heights are representative of the energy levels of detected radioactive particles, said circuitry having means for discriminating and counting the pulses of different heights;
• a portable self-contained power supply operatively connected to said pump and electronic circuitry;
• a readout unit for displaying the working level hours of detected radioactive exposure by the dosimeter;
• means for electrically transmitting the number of counted pulses in the dosimeter to the readout unit when connected thereto;
• and
• means within the readout unit for converting the pulses transmitted to the readout unit into a numerical display of the working level hours of detected exposure based upon a preset standard therein.