Mr. Owen Lucas
Postgraduate Student


  • Advanced certificate in Mechanical Engineering
  • Bachelor of Mechatronic Engineering--The University of Adelaide
  • Currently undertaking a PhD in Laser Diagnostics of Near-arc Welding Fume Formation

PhD: Laser Diagnostics of Near-arc Welding Fume Formation

Today there is an increased importance being placed on health and safety in the work place. This can be attributed to both the economic value and legislative necessity of maintaining healthy staff. Occupational hazards come in many forms, including electrical, physical, acoustical and chemical. In many occupations such as welding, workers are exposed to a combination of several hazards.

One of these is the exposure to fumes, particularly those produced from welding processes involving electrical arcs. The inhalation of welding fume can cause both temporary side effects and longer term health complications. These health effects lower the productivity and quality of life of the welder which in turn costs the employer through reduced worker productivity and potential compensation. Currently the primary method of controlling occupational exposure is by intercepting fume transmission between the welding arc and the welder s breathing zone. Intercepting fume during transmission, however, is not entirely effective or appropriate in many cases. For this reason, alternative methods of reducing fume formation at source with minimal impact on weld quality or productivity would be considered an attractive hazard control measure. Despite fume control at source being considered the preferred method of exposure reduction, little is known about the formation processes involved.

Obtaining an improved understanding of fume formation is an important first step in determining new process modifications that would reduce occupational exposure. Modern laser diagnostic techniques may provide a useful tool to understanding the intermediate chemical processes involved in near arc fume formation. The use of such laser analysis in other fields of research indicates that it could fill gaps in understanding fume formation, complimenting knowledge gained by previous fume measurements and theoretical models. This research sets out to adapt laser diagnostics for the analysis of the near arc region where the majority of the fume is formed. Having developed these techniques they will then be used to detect the formation of chemical components considered important in the evolution of fume. One of the chemical components considered significant is that of nitric oxide which is formed by the heating of atmospheric gasses. It is anticipated that studying the formation of nitric oxide will result in an improved understanding of near arc chemistry and kinetics. Having determined the formation and movement of nitric oxide, it is believed modifications to shielding gas composition and flow rates can be made to reduce the quantity or toxicity of the resultant fume.

G.J. Nathan, P.J. Ashman, Z.T. Alwahabi, O. Lucas, and K. Meeuwissen, A comparison of the spatio-temporal emission of sodium from standard and dewatered Loy Yang coal using PLIF, Proceedings of the Australian Symposium on Combustion & The 8th Australian Flames Days, 8-9 December 2003, Melbourne Australia.

Z. Alwahabi, O. Lucas, K. Meeuwissen and V. Linton,
Laser Polarization Spectroscopy of Gas Tungsten Arc Welding Plasma, In Proceedings of the 11th International symposium on laser aided plasma diagnostics, 28 September - 2 October 2003, Les Houches France .