Restricting the movement of fumes, mists, vapors, particulates and aerosols in laboratory environments is the job of the lab hood. Ensuring the hood is properly used and well maintained is the responsibility of lab employees. This Video On Demand explains how lab hoods work, why it is essential to follow safety protocols while performing procedures within hoods, and the importance of good housekeeping within the hood. Viewers are familiarized with the standard air flow and face velocity tests that must be conducted periodically to ensure chemical lab hoods operate properly. The course describes information relevant to chemical hoods, biohazard hoods and radio isotope hoods. Labs are inherently dangerous places, and workers who use hoods are doing so because the materials in use are hazardous. Ensuring workers use the proper personal protection equipment, understand how to work safely within a hood, practice good housekeeping, and know which hood to use with different materials will go a long way toward providing a safe work environment. This brief video provides an overview of what every lab workers needs to know about working safely within a controlled air environment.