|Description:||This historical photograph was provided by the Center for Disease Control's (CDC), National Institute for Occupational Safety and Health (NIOSH). Reprinted from the February, 1951, ”Industrial Hygiene Newsletter”. The image depicted an apparatus designed to measure sulfur dioxide (SO2) concentrations in the air. This gas is naturally produced as a byproduct of volcanic activitiy, but more importantly, is a byproduct of many industrial plant activities, where the combustion of coal and various petroleum energy sources takes place. Sulfur dioxide released into the atmosphere, when combined with nitrogen dioxide (NO2), gives rise to sulfuric acid (H2SO4), whereupon, in the natural environment, gives rise to the formation of “acid rain”. In the industrial setting, SO2 causes eye and respiratory tract irritation.|
The NIOSH Historic Photo Collection began as the “picture file” of the Industrial Hygiene Division of the U.S. Public Health Service (USPHS), c. 1930-1960. It is a unique collection of mid-20th Century images of American workers and workplaces and documents occupational safety and health research of that era. The collection consists of approximately 1,000 original photographs and schematic drawings.