Ionizing radiation shielding

As with other radioactive substances, exposure to its ionizing radiation can cause cancer. When ingested it tends to accumulate in the liver, kidney, and spleen causing radiation damage from the alpha particles. All operations and handling must be carried out in leak-proof boxes by mechanical means behind thick neutron shields. 

Radiation-Density Gauges Gamma radiation may be used to measure the density of material inside a pipe or process vessel. The equipment is basically the same as for level measurement, except that here the pipe or vessel must be filled over the effective, irradiated sample volume. The source is mounted on one side of the pipe or vessel and the detector on the other side with appropriate safety radiation shielding surrounding the installation. Cesium 137 is used as the radiation source for path lengths under 610 mm (24 in) and cobalt 60 above 610 mm. The detector is usually an ionization gauge. The absorption of the gamma radiation is a function of density. Since the absorption path includes the pipe or vessel walls, an empirical calibration is used. Appropriate corrections must be made for the source intensity decay with time. 

Hazard The most radiotoxic of the elements and one of the most toxic substances known dangerous ionizing radiation persists indefinitely a powerful carcinogen. Must be handled by remote control and with adequate shielding. 

Hazard Highly toxic, emits ionizing radiation. Lead shielding should be used in storage and handling, adequate protective clothing and remote control devices are essential. Destructive to living tissue. 

CEMENTS AND CONCRETES FOR USE IN STRUCTURES DESIGNED TO SHIELD AGAINST IONIZING RADIATION... 

Concrete walls with the capacity to shield against ionizing radiation may be required in atomic power plants and facilities using radioisotopes, X-ray equipment, and the like. 

Shielding Use proper barriers to block or reduce the penetration of ionizing radiation. 

Irradiation sterilization—The use of ionizing radiation for the treatment of infectious waste. Isolation zone—An area adjacent to a physical barrier, clear of all objects that could conceal or shield an individual. 

Any source of energetic ionizing or non-ionizing radiation is potentially hazardous if not used correctly. All UV light sources must be well shielded. Skin and eyes should always be protected from exposure to UV light." ... 

The higher heat loss during the test with liquid nitrogen indicates that the pressure between radiation shields may be higher than read by the ionization gauge on the outer shell. Since the spacing between radiation shields is narrow, the residual gas may be trapped inside the spacer. The pressure drop between... 

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