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[Session 2 : SEMI S6] Ensuring the Safe Use of Flammable Gases in The Semiconductor Industry

3:50 pm - 4:50 pm

The safe handling of flammable chemistries is a critical safety concern in the semiconductor industry. The SEMI S6 test protocol was developed to ensure flammable gases would not be an explosion or fire hazard even under fault conditions. This presentation will explore this methodology in detail.  It will explain the S6 approach and explain how it has been used to effectively protect against these hazards in the semiconductor industry.  An alternative approach has been used recently in using the calculation method of IEC 60079-10-1 and that method will also be explored.  Finally, the two methods SEMI S6 and IEC 60079-10-1 will be compared.  This will be done by explaining the results of SEMI S6 in terms of IEC 60079-10-1.   This comparison will permit conclusions to be drawn about how to most effectively ensure flammable gases are handled safely in the semiconductor industry.



Chris Evanston

President, Salus Engineering International


  • Salus Engineering International, President (July 2009 to Present) Mr. Evanston is both the business and technical lead of this global supplier of SEMI S2 and other industrial equipment safety services.
  • Earth Tech, Senior Program Director (November 1997 to July 2009) Mr. Evanston was both the technical and business manager of the international supplier of SEMI S2 and equipment safety services.
  • Prior Experience - SGS, Engineering Manager (1996 to 1997), Lam Research, Product Safety Engineer (1995 to 1996), ITS Product Safety Engineer (1992 to 1995).  Mr. Evanston has been doing S2 evaluations and managing engineers that do S2 evaluations since 1992.

Standards Participation

  • Co-Chair NA EHS Committee (2005 to Present): The committee that controls the technical content of SEMI S2.
  • SEMI Co-Chair Electrical Safety Task Force (1998 to Present): This group developed SEMI S22
  • IEC TC44 US Tag Member and convener of semiconductor working group (2004 to Present): This group developed IEC 60204-33

Education: BS, University of Colorado at Denver, Electrical Engineering; MA, University of Colorado at Boulder; BS, Illinois State University