Current status of nuclear power in the United States and around the world.

Nuclear energy's share of the world electricity market has been growing over the past 35 years. In 1989, eight generating units entered commercial operation abroad and three new units were licensed in the U.S. In early 1990, Mexico became the 26th country to produce electricity from nuclear power. Currently the 426 operating reactors supply one sixth of the world's total electrical capacity. Fourteen countries have now operated nuclear plants for 20 or more years. Since 1980, France has been the leader in the use of nuclear power and currently generates three quarters of its electricity from 54 nuclear plants. The U.S. has 112 nuclear plants, the largest number of any country in the world. These plants satisfy almost 20 percent of U.S. electrical energy requirements. Last year Three Mile Island, the would-be icon for everything that is wrong with the nuclear industry was rated as the most efficient nuclear plant in the world. The worldwide trend toward acceptance of nuclear is improving slightly, but many political and societal issues need to be resolved. Whereas recent polls indicate that a majority of the people realize nuclear must be a major contributor to the energy mix of the future, many are reluctant to support the technology until the issue of waste disposal has been resolved. Fears of another Chernobyl, lack of capital, and a new anti-nuclear campaign by Greenpeace will keep the nuclear debate alive in many countries. Additional stumbling blocks in the U.S. include the need to develop a new generation of improved reactor designs which emphasize passive safety features, standardized designs and a stream-lined federal licensing process. Nuclear power is really not dead. Even environmentalists are starting to give it another look. A nuclear renaissance will occur in the U.S. How soon or under what conditions remain to be seen. The next crisis in the U.S. will not be a shortage of energy, rather a shortage of electricity.(ABSTRACT TRUNCATED AT 250 WORDS)

Hygiene implications associated with x-ray exposures to dental patients.

An elastic mask worn by patients, then a skeleton encased in plastic, was instrumented with LIF thermoluminescent dosimeters to quantify exposures delivered from full-face diagnostic dental x-rays. Locations of interest included skin surface, eyes, upper and lower teeth and thyroid. Exposures in the 100 mR range were common and a maximum of over 6000 mR was measured in the teeth region during a full-face examination with a periapical unit. In general, exposures received from periapical equipment were several times those obtained from panoramic devices.