Personal protective equipment (PPE) is the specialized clothing or equipment worn by an individual to protect them from exposure to health and safety hazards. In a laboratory environment this can range from safety glasses, gloves, and a lab coat, right through to a Biosafety Level 4 (BSL-4) positive pressure suit. Additional protection is offered by fume hoods and biosafety cabinets, two commonly used pieces of laboratory equipment that significantly decrease the potential for exposure to hazardous chemicals or biological agents.

Fume hoods are designed to remove chemical fumes and aerosols from the laboratory. They use a fan to draw in air through the front of the hood, which is then expelled from the laboratory (ducted fume hoods) or filtered and fed back into the room (recirculating fume hoods). A secondary function of fume hoods is to act as a physical barrier between chemical spills, runaway reactions, and fire.

Biosafety cabinets provide a clean working environment and allow safe handling of biological contaminants and other potentially hazardous materials. They exist in several different forms, depending on the type of containment that is required. Class I cabinets exhibit similar air movement to a fume hood, although the exhaust air must be High Efficiency Particulate Air (HEPA) filtered for environmental protection; class II cabinets vary according to the amount of air that is recirculated within the cabinet, and are selected according to the nature and quantity of materials being used; class III cabinets are suitable for work with BSL-4 agents, providing a gas-tight enclosure with a completely sealed viewing window.

Whether carrying out a chemical reaction within a fume hood, or working with micro-organisms contained by a biosafety cabinet, safe work practices should always be followed. We’ve reached out to the scientific community to bring you three top tips for working with each of these platforms.

Three top tips for working with fume hoods

  • Make sure your fume hood has been calibrated, and that it has a clear marker to indicate the highest sash height that can be used safely. The position of the sash is used to control the velocity of the air that passes through the fume hood, and if the sash is too high fumes can enter the laboratory. When you’re not using the fume hood, close the sash, this will provide containment in the event of a fire or an explosion. Jane Scanlon, Associate Medicinal Chemist at Domainex
  • Any large equipment within the hood should be elevated to allow the air to flow underneath it, and should never obstruct slots or baffles. If you mark a line on the bench surface within the hood, you can ensure that any apparatus is kept at least six inches back from the opening. Kathryn Irons, Medicinal Chemist at Rxcelerate Limited
  • Don’t use the hood for storing laboratory chemicals or chemical waste. Items stored in the fume hood can interfere with air flow and introduce dangerous obstacles that provide potential health and safety risks. It’s also possible that different chemicals may be incompatible with one another, creating unnecessary hazard. Paul Meo, Medicinal Chemistry Program Manager at Discuva

Three top tips for working with biosafety cabinets

  • Make sure to choose a cabinet that’s appropriate for the hazard level; I use a BSL-2 cabinet as I work with agents that may be associated with human disease. I decontaminate it regularly, and the laboratory it’s in has limited access and biohazard warning signs at the door. I always wear a lab coat, gloves and safety glasses while I work. Lynwen James, Laboratory Technician at University of Essex
  • It’s likely that you’ll be spending a lot of time at the biosafety cabinet, for example if you’re plating out cells and treating them with chemical compounds, so make sure that the cabinet is set up as ergonomically as possible. You need good knee/thigh clearance to maintain correct posture (consider the use of foot rests), a good height for moving items in and out of the cabinet, a wide access for forearm comfort (foam armrests can be really helpful), and a nice large work area to promote good aseptic technique. Mark Stockdale, Group Leader, Applied R&D at Horizon Discovery
  • Plan your work carefully so you can disinfect and place all the materials you need to conduct your experiment in the cabinet before you begin working; this will prevent unnecessary movement of items in and out of the cabinet as you work, which could disrupt the airflow. Never place items over the air grilles, and always disinfect the work surface before and after use. Stuart Wood, Research Scientist at Bactevo

Fume hoods and biosafety cabinets are essential pieces of laboratory equipment, carefully designed to protect both personnel and products. By selecting a suitable platform, and using it appropriately, exposure to potentially hazardous materials can be avoided.