Shielding, from ionizing radiation

Ionizing radiation—K-ray or gamma-ray equipment, used to inspect welds, can generate exposures to ionizing radiation from equipment with insufficient shielding and locking mechanisms. Strict adherence to safe radioactive source procedures must be implemented to protect workers from ionizing radiation hazards. 

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. 

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." ... 

Inorganic lead compounds were used in paints and organic compoimds in fuel to increase octane number, until concerns about lead s toxic properties arose. Lead is relatively opaque to ionizing radiation and is a valuable shielding material in X-ray applications and nuclear facilities. Another market for lead is in alloys that are used as solders in applications ranging from circuit boards to heat exchangers. Lead is also used in acoustic barrier panel, glassware and ceramic, and fiber optic cables. 

The expected adverse effects of increased levels of uv-B radiation include increased incidence of skin cancer in fairskinned races, decreased crop yields and a variety of stresses on terrestrial and aquatic ecosystems. Such effects have been considered in the past in connection with possible reduction of the ozone shield by the operation of fleets of SST airplanes [65] and by the continued release of chlorofluoromethanes used as refrigerants and as propellants in aerosol spray cans [66]. The information available is insufficient to allow quantification of most of these effects. Epidemiological data were used in the NAS study [1] to estimate that a 50 % ozone shield reduction lasting 3 years would lead to an increase of skin carcinoma and melanoma of 3-30 % at midlatitudes, with a geometric mean of about 10 %, that will persist for 40 years. This may be compared with the estimate made in the same study that during the first generation a 10,000 Mt war would increase the spontaneous cancer death rate by about 2 % as a result of exposure to low levels of ionizing radiation from radioactive fallout. 

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