OHD delivers occupational health, safety, and industrial hygiene solutions—from respirator fit testing to air sampling, and noise monitoring.

Shop 10,000+ SKUs of high-quality garage door parts and accessories at OHD Parts with free shipping over $1,000, easy reordering tools, and quality service.

Overhead Door™ is a leading provider of door and access solutions for residential, commercial, institutional, and industrial applications. Learn more.

You are alerted as to whether the door changes to the fully open or closed position even if the door is operated manually by disengaging the door from the opener. OHD Anywhere™ delivers …

OHD is leading the standard in Respiratory Fit Testing. We have passionately been protecting the health of the world’s workforce since1992 with our quantitative respiratory fit tester, the OHD Quantifit.

OHD Studios offers comprehensive rentals (gear, studios), plus advanced production services: motion control, virtual production, and creative solutions. Elevate your project.

OHD manufactures and distributes Health & Safety equipment worldwide. From the OHD QuantiFit2 mask fit tester to noise monitoring, spirometers, audiometers and much more!

Our founder, C.G. Johnson, created the original upward-acting garage door in 1921 and the first electric garage door opener in 1926. Since then, Overhead Door Corporation remains an innovator, …

OHD QuantiFit 2™ Respirator Fit Testing System is a highly specialized instrument that utilizes OHD's scientifically proven and patented Controlled Negative Pressure (CNP) technology to directly …

OHD is a company committed to our Mission of Passionately Protecting The Health Of The World's Workforce. OHD provides a range of products and services to help you protect your employees and...