Radiation portal monitor

Recognizing that nuclear materials are widely available and the terrorists interests in radiological and nuclear devices, the United States Congress appropriated 300 million to the Department of Homeland Security to install radiation detectors at U.S. borders. Through 2005, DHS had installed 470 radiation portal monitors throughout the country including mail facilities and land and sea entries into the United States. The U.S. has also supported the installation of detectors at the borders of the states of the former Soviet Union through its Departments of State,... 

Portal monitors Detect ionizing radiation at transportation portals Solid scintillation Geiger-Muller counter... 

A frisker type hand held radiation meter may be used to survey low levels of contamination and may be used to demonstrate the use of a portal monitor. If a whole body counter is available, student monitoring can be a useful experiment. It can be performed with and without radioactive materials concealed in or on clothing (e.g., lantern mantels, or other available unlicensed materials.) The same can be performed with hand held survey meters, perhaps allowing one group to hide sources and another group to find them. 

A. 1207. This section shall describe the radiation and contamination monitoring stations, including fixed hand and foot monitors, portal monitors (if used) and portable activity monitors located at these stations. The portable and laboratory equipment and instrumentation for performing radiation and contamination surveys, for contamination control between different access zones, for airborne radioactivity monitoring/sampling and for personnel monitoring shall also be described. 

Rapiscan Systems manufactures and markets the Secure 1000 X-ray system [57], Figure 9 shows the Secure 1000 system. Typical scan time (for one side of the subject) for this portal is 8 s or less with a radiation level of 10 microREMs. The Secure 1000 provides images of concealed items such as explosives, narcotics, weapons (including plastic, ceramic, and composite), and metals. A color image is presented to an operator s monitor for review. Figure 10 shows an image from the Secure 1000. 

The radiation monitoring system was designed to allow continuous monitoration of radiation levels inside the critical facility. It is composed by 27 radiation monitoring channels, being 14 area monitors, 8 process monitors, 3 air monitors, 1 hand and foot monitor and 1 monitor of the "portal" type. 

---