There are essentially two technologies for quantitative respirator fit testing: ambient aerosol technology, which uses particle-based counting and controlled negative pressure (CNP) technology, which uses air to challenge the...

OHD is committed to the research and future development of Respiratory Protection. That is why we have recently partnered with the University of Minnesota and their Environmental Health and Safety Department.

Every day at OHD we strive to protect those who protect us! We accomplish that by developing and offering industry-leading health and safety instruments that protect the world’s lungs, hearing, and vision. To succeed in this...

OHD is committed to the research and future development of Respiratory Protection. That is why we have recently partnered with the University of West Virginia and their Department of Industrial and Management Systems.

OHD has proudly been partnered with the Chicago Fire Department for over 5 years.