DescriptionThe Federal Industrial Hygiene Agency.pdf
English: "The Federal Industrial Hygiene Agency: A History of the Division of Occupational Health, United States Public Health Service", Prepared by Henry N. Doyle, Sanitary Engineer Director, Retired
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (50 p.m.a.), Mainland China (50 p.m.a., not Hong Kong or Macao), Germany (70 p.m.a.), Mexico (100 p.m.a.), Switzerland (70 p.m.a.), and other countries with individual treaties.