THE EFFECTS OF WELDING PARAMETERS ON ULTRAVIOLET-LIGHT EMISSIONS, OZONE AND CR-VI FORMATION IN MIG WELDING

This paper describes the relationships between ultra-violet emission, ozone generation and Cr-VI production in MIG welding which were measur ed as a function of shield gas how rate, welding voltage, electrode st ick-out and shield gas composition using an automatic welding rig that permitted MIG welding under reproducible conditions. The experimental results are interpreted in terms of the physicochemical processes occ urring in the micro- and macro-environments of the are as part of rese arch into process modification to reduce occupational exposure to ozon e and Cr-VI production rates in MIG welding. We believe the techniques described here, and in particular the use of what we have termed u.v. -ozone measurements, will prove useful in further study of ozone gener ation and Cr-VI formation and may be applied in the investigation of e ngineering control of occupational exposure in MIG and other welding p rocess such as Manual Metal Arc (MMA) and Tungsten Inert Gas (TIG). (C ) 1997 British Occupational Hygiene Society.