A variety of smokes and obscurants have been developed and used to screen armed forces from view, signal friendly forces, and mark positions. Smokes are produced by burning or vaporizing particular products. Obscurants are anthropogenic or naturally occurring particles suspended in the air. They block or weaken transmission of particular parts of the electromagnetic spectrum, such as visible and infrared radiation or microwaves. Fog, mist, and dust are examples of natural obscurants. White phosphorus and hexachloroethane smokes are examples of anthropogenic obscurants. The U.S. Army seeks to reduce the likelihood that exposure to smokes and obscurants during training would have adverse health effects on military personnel or civilians. To protect the health of exposed individuals, the Office of the Army Surgeon General requested that the National Research Council (NRC) independently review data on the toxicity of smokes and obscurants and recommend exposure guidance levels for military personnel in training and for the general public residing or working near military-training facilities.

General Kenney Reports is a classic account of a combat commander in action. General George Churchill Kenney arrived in the South- west Pacific theater in August 1942 to find that his command, if not in a shambles, was in dire straits. The theater commander, General Douglas MacArthur, had no confidence in his air element. Kenney quickly changed this situation. He organized and energized the Fifth Air Force, bringing in operational commanders like Whitehead and Wurtsmith who knew how to run combat air forces. He fixed the logistical swamp, making supply and maintenance supportive of air operations, and encouraging mavericks such as Pappy Gunn to make new and innovative weapons and to explore new tactics in airpower application. The result was a disaster for the Japanese. Kenney's airmen used air power-particularly heavily armed B-25 Mitchell bombers used as commerce destroyers-to savage Japanese supply lines, destroying numerous ships and effectively isolating Japanese garrisons. The classic example of Kenney in action was the Battle of the Bismarck Sea, which marked the attainment of complete Allied air dominance and supremacy over Japanese naval forces operating around New Guinea. In short, Kenney was a brilliant, innovative airman, who drew on his own extensive flying experiences to inform his decision-making. General Kenney Reports is a book that has withstood the test of time, and which should be on the shelf of every airman.

This document is a compendium of scientifically valid and accepted methods that can be used to assess sediment quality and predict ecological impacts...the intent here is to provide the most useful overall measures or predictors of ecological impacts currently in use rather than procedures that may have limited application outside of a particular regulatory framework... parag The information provided in the compendium on the relative strengths and weaknesses of the different assessment methods can provide assistance in selecting the appropriate methods.