Mr. Chan has 25 years work experience in waterworks in Hong Kong. He joined Water Supplies Department, Hong Kong SAR Government in 1981 and retired in 2016. He was the Senior Waterworks Chemist in the period 1981-2008 and the Chief Waterworks Chemist from 2008 to 2016. Mr. Chan has extensive experience in waterworks in Hong Kong, he is familiar with various water treatment processes, the operation of different analytical instruments and the requirements for laboratory accreditation. Mr. Chan has extensive experience of quality assurance and was a technical assessor for HOKLAS for 15 years.