Welding shops for educational facilities, whether they are part of a high school technology program or a technical college, are significantly different from industrial welding operations. In the educational setting, the purpose of the programs is solely to teach the student to become proficient in various types of welding and maybe specialize in advanced welding techniques after the basics have been mastered. Students are typically in a welding class for a few hours a day or maybe even just a few hours per week. In industry, a welder is employed by a company where they are often required to weld daily for extended periods of time. Recognizing that there is a difference in the levels of exposure to welding fumes, the question that must be answered by the design professional is, should the ventilation requirements for the educational environment be relaxed as compared to the ventilation requirements for the industrial environment, and, if so, how much and what do governmental regulations have to say about this issue? Instinctively one might answer that the regulations should be applied similarly to both, but that is clearly not reflected in current design practices.
Welding fumes aren’t good to breath, and all regulatory agencies agree that welding fumes should be directed away from the welder’s breathing zone when local exhaust ventilation (LEV) is being used. While all fumes are bad, some fumes are recognized as more hazardous than others. One such fume is hexavalent chromium, which is produced when welding stainless steel and other materials containing chromium. During the welding process, the chromium is heated, oxidation occurs, and it is converted into hexavalent chromium. Hexavalent chromium is also designated by the following: chromium (VI), hexchromium, Cr (VI), Chromium + 6, and Cr + 6. It is classified as a carcinogen. There are other elements present in some welding fumes, such as manganese, that are also very harmful, but hexavalent chromium has gotten most of the attention over the past 25 years as the result of the extensive use of stainless steel in various industries including the nuclear industry, water treatment industry, and many others.