Because they are commissioned officers, they can be classified as prisoners of war under the Geneva Conventions, if captured by a belligerent entity. The United States Coast and Geodetic Survey (USC&GS), a predecessor to NOAA, originally began commissioning its officers so that if captured while engaged in battlefield surveying, they would be protected under the Law of Armed Conflict and could not be tried or executed as spies. The USC&GS Commissioned Officer Corps became the Environmental Science Services Administration Corps (ESSA Corps), upon the creation of the Environmental Science Services Administration (ESSA) on 13 July 1965, then became the NOAA Corps upon the creation of NOAA on 3 October 1970. The PHS traces its origins to a system of marine hospitals created by "An Act for the relief of sick and disabled seamen", passed by Congress in 1798; it adopted a military model of organization in 1871. Informational notes Citations