Independent Principal Consultant

Bill Pearson - Water Treatment ProfessionalBill is a Certified Water Technologist (CWT) with over 40 years of experience in the water treatment industry. Bill specializes in Legionella risk management.

Bill is a member of the American Chemical Society (ACS) and the National Association of Corrosion Engineers (NACE International). He currently serves as Liaison for the Association of Water Technologies (AWT) to the American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE), and the Cooling Technology Institute (CTI). He is chair of the Legionella Task Force at AWT, and serves as the organizational representative voting member for AWT on the NSF Standard 444 (Legionella) joint committee.

In addition, Bill has served on AWT task forces to the American Society for Healthcare Engineering (ASHE) and the U.S. Green Building Council (USGBC). He is a past chair of the ASHRAE Water Treatment Technical Committee, and is an Executive Committee member on the ASHRAE (188) Legionellosis SSPC and voting member on the CTI (159) Legionellosis committee.

Bill is a past chair of the AWT Technical Committee, served on the AWT Board of Directors, and was President of AWT in 2003. He received the prestigious Ray Baum Memorial Water Technologist of the Year Award in 2005.

In January 2018, Bill joined the AWT “Faculty” that teaches the AWT Technical Training Seminars given annually at Eastern and Western US locations. The subject matter of the course Bill is teaching is on Legionella as a technical knowledge discipline for the Water Treatment Professional.

Do you have a complex water treatment problem, or are you looking for an experienced water treatment consultant to provide independent advice? Feel free to contact AFA for a free initial consultation. If you would like a PDF version of one our consultant’s resumes, please contact us via email or phone.

Email us at or call us at (630) 364-3965

  • January 2018: Bill joins AFA as a Principal Consultant to provide Legionella Risk Management, Expert Witness, and Water Treatment Consulting Services.
  • April 2016: Bill joined Special Pathogens Laboratory as Senior Vice President of Business Development to advance an affiliate program for the water treatment professional and industry with specialized Legionella risk and water management plan resources.
  • September 1975: Bill began his water treatment career at Southeastern Laboratories, Inc. as a Chemist & Product Specialist; Technical Sales & Service Specialist; Technical Director to the Director of Consulting & Technical Services. In 1989 he became Executive Vice President and Director of Sales, Consulting & Technical Services – serving those roles through March of 2016.
  • Biology/Medical Biochemistry graduate from East Carolina University
  • Certified Water Technologist (CWT)
  • American Chemical Society (ACS)
  • American Society of Healthcare Engineering (ASHE)
  • American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE)
  • Association of Water Technologies (AWT)
  • Cooling Technology Institute (CTI)
  • International Water Conference (IWC)
  • National Association of Corrosion Engineers (NACE)

Bill has written many publications covering various aspects of water treatment and Legionellosis, and is the primary author of the AWT Legionella document.

  • Successfully Managing the Risk of Legionellosis Using ASHRAE Standard 188-2015; ASHRAE Learning Institute (ALI), June 2016 – subsequent publications as ALI short-course presentations by Bill Pearson in the U.S. and Internationally, 2017
  • Risk Management for Legionellosis; ASHRAE JOURNAL, October 2015.
  • Legionellosis Standard Provides Guidance on Risk Management Requirements; Water Quality Products, July 2015.
  • AWT’s ASHRAE Liaison Report on 1361-RP: Biological Control in Cooling Water Systems Using Non-Chemical Water Treatment Devices; AWT, October 2010.
  • Legionella – An Environmental Issue and Concern; Journal of Environmental Health, January 2004.
  • Legionella 2003: Domestic Plumbing (Potable Water) Systems and Legionnaires’ Disease; Water Technology News – Industry Insight, January 2004.
  • Legionella & Legionnaires’ Disease – Are You Informed?; Pollution Equipment News, February 2004.
  • Legionella 2003: An Update and Statement by the Association of Water Technologies; Association of Water Technologies, June 2003.
  • Legionella: An Update and Statement by AWT; Association of Water Technologies, July 2000.

Bill has contributed to numerous technical manuals, reviewed and presented papers, conducted educational training workshops and seminars, chaired committees and moderated sessions. Bill also served as instructor for the Water Treatment segment of the regional NCSU Boiler Efficiency Workshops conducted by Dr. Herb Eckerlin, Professor, Mechanical & Aerospace Engineering, at North Carolina State University.