Biological Safety Cabinets: Improvements in Efficiency and Ergonomics
The phrase “biological safety cabinet” sounds straightforward enough. It’s clearly a cabinet meant to keep biological hazards safely contained. This technology, though, comes in a broad range of classes.
Seeking improvements in efficiency and ergonomics
The phrase “biological safety cabinet” sounds straightforward enough. It’s clearly a cabinet meant to keep biological hazards safely contained. This technology, though, comes in a broad range of classes: Class I; Class II, Type A1 and Type A2; Class II, Type B1 and Type B2; and Class III. The different types of biological safety cabinets must meet different specifications and work in different applications. For example, Class I and II cabinets can be used with moderate- and high-risk microorganisms while Class III cabinets are totally enclosed, thereby providing the highest level of protection. Consequently, Class III cabinets tend to get used in research at biosafety level (BSL) 3 or 4 labs. The Class I cabinets protect the worker and environment, while Class II and III cabinets protect the product as well.
Marina Cassin, U.S. representative for ADS Laminaire (Chicago, IL), says that the Class II Type A2 or B2 makes up the most common biological safety cabinets. Overall, cabinets get used in biological research labs, pharmaceutical companies, hospitals, and more.
Minimizing the maintenance
Most facilities provide specific guidelines for when a biological safety cabinet should be recertified. For example, it might need recertification once a year or anytime it gets moved. Any suspicion of malfunction should also trigger recertification. In some cases, changing the type of research being done also requires the instrument to be certified again. In addition, BSL-3 and BSL-4 labs often certify biological safety cabinets every six months.
Nonetheless, Wayne Wood, associate director for safety at McGill University (Montreal, Canada), says, “It is very expensive to be testing and certifying them so often—annually—and from a safety point of view, that is not so reliable. Ideally, they should have the technology to analyze and detect failures rather than wait for that once-a-year visit from a technician. If something happens the day after certification, a cabinet can run almost a whole year with a faulty HEPA [filter] and nobody will know.” Consequently, newer cabinets include improvements in leak detection in the HEPA filter.
Cassin points out that some manufacturers hope to simplify the maintenance. For example, she says, “Sometimes it’s a nightmare to change the filters, and we’re trying to make that easier.”
In addition, best practices dictate that a biological safety cabinet gets cleaned and disinfected before and after every use. Even the ease of cleaning a biological safety cabinet depends on the design. Marian Downing, biological safety project manager at Alliance Biosciences (Richmond, VA), says, “I don’t have a problem with most biological safety cabinets, but I have seen some with perforated work surfaces and/or the work surface split in half down the middle. I don’t think those are very practical for spill cleanup, since liquids will leak down underneath the main work surface.
Enhancing the operation
A better biological safety cabinet should also be easier to use, but that’s not always the case. As Wood says, “My second biggest beef is ergonomics, as there is very little, if any, adjustability built into the cabinets to accommodate the different needs of users. We are still not able to genetically engineer our people to fit the biological safety cabinets, so until we are, the manufacturers have to do a better job in engineering their cabinets to fit the people.”
The manufacturers agree. Brian Raymond, sales and marketing manager at Microzone Corporation (Ottawa, Ontario), says, “One of the biggest trends is focusing on ergonomics.” As examples, he mentions the addition of armrests and/or supports that “can be an add-on at the time of order or offered as an after-market installation.” He also notes that adjustable-base support stands and footrests are requested quite often. The trends in ergonomics even include positioning the cabinet relative to overhead lighting. “Consideration as to where the cabinet is placed within the lab or room can reduce the glare off the glass face shield,” Raymond says. “Some companies have gone as far as to add special coatings to the glass to reduce glare.”
Raymond also points out the trend to make biological safety cabinets more efficient. “The motor is the biggest energy draw,” he says, “but ECM [electrically commutated motor] technology increases a motor’s efficiency and longevity.” He notes that even the type of lighting inside a cabinet can help improve its efficiency.
Trends in biological safety cabinets also involve the users. “One big push these days is for hands-on biological safety cabinet training with a competency test at the end,” says Downing. “Not many places are doing this yet, but it is an eye-opener since most people think they know how to work in a cabinet but are not doing it correctly.” For example, she says that trainers should demonstrate airflows in a biological safety cabinet with dry ice, incense, or a smoke stick. “This is very informative for trainees who will understand why they are supposed to work in the rear of the cabinet, avoid crossing their arms or covering the front/back grillwork while they are working in the cabinet, etc.”
So the trends in biological safety cabinets range from various aspects of the technology to its implementation. By building more advanced devices, the technology operates more efficiently and safely. Nonetheless, users must properly maintain these cabinets—from having them certified as required to keeping the filters changed on schedule. The use goes beyond maintenance to the actual way that scientists work in the cabinets. Given the danger that can result from a mistake, it pays to use these cabinets properly. That also creates a line between manufacturer and user because a more ergonomic biological safety cabinet should reduce risks associated with working long hours in an uncomfortable position. Improving comfort improves safety.
Mike May is a freelance writer and editor living in Austin, TX. You can reach him at mike@techtyper.com.
For additional resources on biological safety cabinets, including useful articles and a list of manufacturers, visit www.labmanager.com/biosafety-cabinets