Lew Harriman is retired, after 33 years as Director of Research & Consulting at Mason-Grant in Portsmouth, New Hampshire. He is a Fellow and Life Member of ASHRAE, and his career was focused on humidity control systems in a broad variety of residential, commercial, industrial and institutional applications. - - - - Lew was the lead author of both ASHRAE's Humidity Control Design Guide and the ASHRAE Guide for Buildings in Hot & Humid Climates. He served as Chair of ASHRAE Technical Committee 1.12 (Moisture Management in Buildings), and as the lead consultant for the Malaysian Ministry of Health's recently published "Guidance for Avoiding Mold in Healthcare Facilities." He also served as Principal Consultant to the U.S. EPA for their 2018 "Guidance for Air Cleaners in the Home" and the landmark 2013 "Moisture Control Guidance for Building Design, Construction and Maintenance." Lew has lectured on the subjects of humidity control, thermal investigation of building enclosures and remote monitoring of building assemblies and residential air filtration to more than 5,000 professionals in North America, Asia, Europe and the Caribbean.