'Studies on Hexavalent Chromium Emissions When Welding Stainless Steels

Background: 

When joining or cladding stainless steel alloys, hexavalent chromium or Cr (VI) is one of the welding fume constituents that must be controlled to provide safe working environments and to meet industry regulation requirements.  Although there are various compounds and other constituents in stainless steel welding fumes, this paper only addresses issues with Cr (VI).  Also, this paper does not include the many options for controlling fumes by extraction methods or personal protective equipment.

Abstract:

Various stainless steel welding products and processes were evaluated to determine their potential Cr (VI) emission rates.  Comparisons were made to help end users select the optimum solution for their welding application and fume control.

Welding fume generation rates and analyses were done using Gas Metal Arc Welding (GMAW), Flux Cored Arc Welding (FCAW), Metal Cored Arc Welding (MCAW), and Shielded Metal Arc Welding (SMAW) processes. Stainless steel electrodes in the ferritic, austenitic, martensitic, duplex, and super duplex grades were used for these tests.

The effects on Cr (VI) emission rates were studied for different welding consumable slag systems, product designs and welding parameters.  Shielding gases and their effects on Cr (VI) emission rates were also evaluated for the GMAW, FCAW, and MCAW processes.