We may summarize in this way. Our knowledge of the effects from the fallout is deficient. We cannot say exactly how many lives may be impaired or shortened. On the other hand, our knowledge is sufficient to state that the fallout effect is below the statistically observable limit. It is also considerably less than the effect produced by moving from sea level to an elevated location like Denver, where cosmic radiation has a greater intensity. It is also less than having a chest X-ray every year. In other words, we know enough to state positively that the danger from the world-wide fallout is less than many other radiation effects which have not worried people and do not worry them now. We have compared radiation from the fallout with radiation from other sources. It is also possible and helpful to compare the fallout danger with different kinds of dangers. For this purpose it is convenient to express all dangers in terms of a reduced life-expectancy. For example, smoking one pack of cigarettes a day seems to cut one’s life-expectancy by about 9 years. This is equivalent to 15 minutes per cigarette. That cigarettes are this harmful is, of course, not known with certainty. It is a “best guess,” due to Dr. Hardin Jones, based on an analysis of statistical data. A number of Dr. Jones’ statistical findings are listed in the following table:[13] _Reduced Life Expectancy_ Being 10 per cent overweight 1.5 years Smoking one pack of cigarettes a day 9 years Living in the city instead of the country 5 years Remaining unmarried 5 years Having a sedentary job instead of one involving exercise 5 years Being of the male sex 3 years Automobile accidents 1 year One roentgen of radiation 5 to 10 days The world-wide fallout (lifetime dose at present level) 1 to 2 days The reader will see that the world-wide fallout is as dangerous as being an ounce overweight or smoking one cigarette every two months. [Illustration: How people get radiation Average dose in roentgens per year]