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Members of the Advisory Committee

Providing constructive challenge to the Board in an advisory and support role

The Advisory Committee offers advice and support, providing constructive challenge to the Board and complementing Board skills. All Advisory Committee members have knowledge and experience of IH/OH work globally and a demonstrable interest in the objectives and work of OHTA. The Advisory Committee is jointly chaired by Michael Connor and Dr Sharann Johnson. 

Mr Jason Hodgkiss

Jason has 29 years of experience in Occupational Hygiene and is registered in the UK Register of Expert Witnesses. His principal area of expertise is in asbestos. From 2003 Jason served as Director responsible for the Occupational Hygiene/Environmental offering of STATS Limited, a diverse company offering occupational hygiene, environmental, ground and civil engineering, geophysical surveying, materials in buildings, structural investigation, and laboratory services.  In 2012 he established an independent consultancy On Advice Limited.  Also in 2012 Jason became the BOHS Regional Organiser for the East Anglia region of the UK, although this role is being handed over in April 2019 due to other BOHS commitments, as he has been serving on the Faculty Board since 2018. As a personal profile, he played Rugby for 15 years, and is currently the Chair of Trustees of a local charity Norfolk Family Carers.  Following on from 9 years service in the Retained Duty System for Northants Fire and Rescue Service, he is currently a Firefighter at his local training airfield.  Additionally, he rides motorcycles for Norfolk Blood Bikes, a charity transporting blood products and urgent samples between hospitals and laboratories.

Mr Sven Hoffmann, Program Manager, MAS Work+Health

Sven Hoffmann is currently Program Manager of the Swiss MAS Work+Health at the University of Zurich and University of Lausanne. He is an occupational hygienist, chartered workplace ergonomist (CREE) and an officer for disaster risk reduction in the Swiss humanitarian aid unit. His further academic education/training includes Risk & Crisis Communication, Didactics and Hazmat life support. His Board experience includes the European Association of Schools of Occupational Medicine (EASOM), the Swiss Ergonomics Association (SwissErgo) and the Centre of Registration of European Ergonomists (CREE). 

Dr Sharann Johnson, FAIOH, COH 

Sharann has worked at the nexus of occupational hygiene, occupational health and product stewardship for over 30 years. Initially, as corporate hygienist for BP Australia she worked with oil and mining operations.   Following a secondment to London with BP Oil Group, she completed her career as a HSE Manager in European and Asian businesses. Sharann now is a consultant to the mining sector. Sharann was 2009 AIOH President and is currently on the AIOH Certification Board and IOHA NAR Committee. Sharann has achieved certification by the AIOH, BOHS and ABIH in past years. She is a AIOH Fellow and AIOH Pam de Silva Awardee for contributions to occupational hygiene.

Mr Mark Katchen, CIH, FAIHA

Founder and Managing Principal at The Phylmar Group, Inc., Mr Katchen has more than 35 years of experience in industrial hygiene, environmental and occupational health, toxicology, risk communication, and international business management. He is Chair of the OHTA Scholarships Committee, Chair of the Joint Industrial Hygiene Ethics Education Committee, Past Chair of the AIHA International Affairs Committee and has extensive international experience.   

Mr Terry McDonald CFFOH

Terry McDonald is a retired academic specialising in developing and running distance learning BSc and MSc programmes in Occupational Hygiene and Occupational Health and Safety. He is a Fellow of the Faculty of Occupational Hygiene, a Chartered Occupational Hygienist, a qualified ergonomist and a retired Chartered Safety Practitioner. He also served as the Faculty of Occupational Hygiene Chief Examiner before retiring. He was a founder member of OHTA management team and was responsible for designing and setting up the OHTA examination and qualification scheme. 

Maharshi Mehta, CIH, CSP, FAIHA 

Maharshi has 30+ years of experience in industrial hygiene conducting industrial hygiene, safety assessments and EHS audits at 300+ workplaces in 30+ countries. He started India’s 1st Master in Industrial Hygiene Program and also Central Industrial Hygiene Association (CIHA, India).  Maharshi has conducted more than 100 training programs and webinars on industrial hygiene, process safety, laboratory safety and other related subjects. He has a Master’s degree in Occupational Safety from University of Cincinnati.  Maharshi is recipient of two President’s awards from AIHA.

Dr Deborah Nelson, CIH 

Dr Nelson is currently President of the American Industrial Hygiene Association (AIHA). A former professor at the University of Oklahoma, she has held various senior management IH/OH regulatory roles within organisations such as the US Environmental Protection Agency, the Geological Society of America, and most recently the US Department of Agriculture, Veterinary Services.

Ms Lydia Renton, CIH, ROH, FAIHA

Lydia Renton  is Director, Occupational Hygiene, Safety and Security with BluMetric Environmental Inc., an engineering and consulting firm headquartered in Ottawa, Canada. She brings career experience from Nortel, and federal and provincial governments. Her work experience is mostly Canadian, but also U.S.A., central Asia, Europe and Africa. Lydia was awarded the Hugh Nelson Award of Excellence from the OHAO (2008), and is a recognized Cyanide Code auditor for the International Cyanide Management Code for gold and silver mining operations.


Lydia served on the Board of Directors of the Ontario WHSA (Workplace Health and Safety Agency) 2000-2002 as an Order in Council appointment. She has volunteered on boards and was the President of the Canadian Registration Board of Occupational Hygienists (CRBOH),  Past Chair of the American Board of Industrial Hygiene (ABIH) Board of Directors and past Chair of the AIHA Fellows SIG. She is currently on the international Board of Directors for Workplace Health Without Borders (WHWB), Chair of the AIHA International Affairs Committee (IAC), and previously served on the OHTA Qualifications Committee (2009-2013). Lydia is co-Chief Oral Examiner for CRBOH, and an AIHA Distinguished Lecturer.

Dr Jas Singh, CIH    CEO, JAS International, LLC

Dr Jaswant (Jas) Singh has practised Occupational Hygiene for the past five decades, 43 of those years as a Certified Industrial Hygienist (CIH) by the American Board of Industrial Hygiene (ABIH).  For the past 15 years, he has focused mainly on International OH issues providing consulting services in dozens of Asian and Middle Eastern countries in addition to his assignments in the USA.

Dr Singh has served as a director of the American Industrial Hygiene Association (AIHA) and ABIH, and as president of the Academy of Industrial Hygiene. His current focus is on teaching Industrial Hygiene in the Middle East and African countries.


Dr. Albert J. Tien 

Dr. Albert J. Tien has over 30 years of experience within the USA and internationally dealing with Sustainable Development and Business Risk Management. Presently he is Managing Partner of the international consultancy, 2TSustainAbility, President Emeritus for the non-profit Workplace Health Without Borders-US, and a Rotarian. He has studied environmental and occupational health issues ranging from the source and spread of Yersinia enterocolitica and related species as a causative agent of gastroenteritis; Indoor Air Quality issues caused by adhesives, paints and fungi; monitored the long-term effects of exposure to Portland cement dust on a cohort of 4000 cement workers across Europe and Turkey; and  identified/evaluated new technologies to treat hazardous or infectious wastes. Additionally, Dr. Tien provides EHS and Sustainable Development services for large corporations as well Developmental Financial institutions and Commercial Signatory Banks to the Equator Principles. He has served on Industry taskforces and NGO advisory committees/Boards for occupational health and safety. He has helped develop and teach courses in Global Occupational Health and Industrial Hygiene. Dr. Tien holds a BS in Biological Chemistry from Tulane University, MS in Life Sciences from New Mexico Highlands University, PhD in Environmental Microbiology/Biotechnology from the Swiss Federal Institute of Technology, Zurich.  His Post-doctoral studies were with the Oakridge Institute for Science and Engineering, and Business studies at St. Gallen University and the International Institute for Management Development (IMD) in Lausanne, Switzerland. 

Dr Alex TSE Chun Kuen, CIH, RPH

Dr TSE is the Programme Director for the Open University of Hong Kong. He is a member of the RPH Registration and Examination Board and Honorary Advisor of the Institution of Occupational Safety and Health (Hong Kong Branch).  He was a former chair of the Institution of Occupational Safety and Health (Hong Kong Branch). He has more than 20 years of solid experience in occupational hygiene, occupational safety and environmental protection in higher education institutes. 


Advisory Committee

  • Michael Connor
  • Sharann Johnson
  • Jason Hodgkiss
  • Mark Katchen
  • Terry McDonald
  • Deborah Nelson
  • Lydia Renton
  • Jas Singh
  • Albert Tien
  • Alex TSE Chun Kuen