Everyone should be familiar with the hierarchy of hazard control – elimination, substitution, engineering controls, administrative controls, and personal protective equipment. When selecting appropriate engineering controls, it is critical to install the appropriate equipment to control the hazards present in the work place.
Fume hoods, biosafety cabinets, glove boxes, and source point ventilation equipment all operate differently and control hazards in their own way. Biosafety cabinets provide both personnel protection and product protection. Most biosafety cabinets recirculate HEPA filtered air back into the room, which is why they are not appropriate for controlling chemical hazards. Chemical fume hoods are exhausted to the exterior of the building. Fume hoods are often utilized for controlling chemical hazards, but may not be appropriate for controlling powders. Glove boxes may be necessary when working with hazardous powders and other substances requiring a more controlled environment. The limitations of source point ventilation equipment such as snorkel vents, elephant trunks, and drop vents must be adequately evaluated when considering installation and use.
A thorough risk assessment or job safety analysis should be conducted for all processes and procedures involving hazardous materials. These assessments will determine the appropriate engineering control necessary for the materials in use.
When relocating or renovating laboratory space, be sure to address the engineering control needs for each lab and ensure that the HVAC system is capable of handling the necessary equipment.