High modernism Cities

Yield Strength of a nuclear weapon, usually expressed in tons of TNT. The bomb dropped on Hiroshima, Japan in 1945 had a yield of approximately 15,000 tons (15 kilotons) of TNT. Modern high-yield weapons have yields >1000 kilotons of TNT. The 4000 lb ammonium nitrate bomb used to blow up the Oklahoma City Federal Building in 1995 was equivalent to about 1.5 tons (0.0015 kilotons) of TNT. 

Tucker and his advisors developed a new strategy for smoke control, focused on the fuel rather than the combustion process. After a severe pollution episode on November 28, 1939, regulations were put in place that allowed only high-grade coal to be burned. Boilers had to be modernized. With these rules strictly enforced, St. Louis by the winter of 1941 could boast of a 72% reduction in visible smoke. Other industrial cities such as Pittsburgh and Cincinnati would follow its lead after the war.5... 

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