FAQ:
Frequently Asked Questions | RoboVent FAQs
< Back to FAQ Home Page| I am hearing a lot about “Manganese”. What is this, and are there new laws coming that will affect production welding operations? |
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Manganese is a trace element found in the emissions of virtually all types of welding. OSHA’s current PEL (Permissible Exposure Limit) stands at 5 milligrams per cubic meter for manganese, and is classified as a ceiling measurement ( 5 mg/m3 (c)). This means that an employees can at no time during his/her workday be exposed to respirable manganese fume in quantities greater than 5 mg/m3. This information can be found through the U. S. Department of Labor’s web site.(1910.1000 Table Z-1 Limits for Air Contaminants, listed as Manganese fume (Mn) Cas No. 7439-96-5). However, the ACGIH (American Conference of Governmental Industrial Hygienists), a highly respected independent board that is not part of OSHA or the government, has recently tabled a motion to lower their recommended TLV-TWA (Threshold Limit Value-Time Weighted Average) to 20 micrograms or 0.020 milligrams per cubic meter. Plainly stated, ACGIH’s potential new exposure limit would be 250 times lower than the current OSHA Limit. Justification for the updated exposure limit is based on recent data that suggests that exposure to Manganese can cause a condition called Manganism, similar to Parkinson’s disease. In extreme cases, overexposure to Manganese fumes can affect the Central nervous system and change neuropsychological and neurobehavioral function. It is widely expected that OSHA will follow the ACGIH recommendation at some point in the not-too-distant future, raising the bar considerably for weld fume control systems. |
