 They noted a precipitous reduction in food availability as well, dropping from about 2,000 calories per day at the start of the war, to 1,680 for industrial workers at the height of the campaign, and less for non-essential workers.The Survey dedicates a separate section of the reports to the atomic bombings of Hiroshima and Nagasaki.They noted that although the blast wave was of about the same pressure as that of a high-explosive bomb, the duration of the effect was longer and that brick buildings were collapsed as far as 7,300 feet at Hiroshima and 8,500 feet at Nagasaki, while traditional wood houses were about the same, while reinforced-concrete structures suffered structural damage or collapse up to 700 feet at Hiroshima and 2,000 feet at Nagasaki.