Air movement visualization in the workplace: Current methods and new approaches

Airflow visualization in the workplace to assess containment, ventilation, or general air movements is often carried out using smoke tracers. The most prevalent method uses a disposable smoke tube that generates a plume of co ncentrated sulfuric acid fume. However, use of the smoke tube exposes occup ational hygienists to the risk of sulfuric acid exposure through inhalation or dermal contact, as well as injury from sharps. Following concern over t he potential health hazard associated with smoke tube usage, alternative fl ow visualization methods and technologies have been reviewed. Methods of ge nerating smoke or bubbles other than using smoke tubes suitable for visuali zing air movements include heated element smoke generators, combustion gene rators, generation of metallic chlorides and ammonium chloride, generation of neutral density bubbles, and water fog generation, Some of these methods are applicable in specific workplace situations. However, there is no comm ercially available smoke or bubble generator currently available that match es the smoke tube for cost effectiveness, ease of use, and wide applicabili ty, while also reducing the potential health risks associated with smoke tu be usage. Despite this, certain technologies, in particular water/glycerol smoke generation using heated element generators, have the potential to be developed into viable alternatives to the smoke tube. Thus, with further de velopment, an air movement visualization method that poses a significantly lower health hazard than the smoke tube is feasible.