Any scientific lab setting witnesses droplets and aerosols, which can be biohazardous if they spread. To control such incidents and create a safe environment for workers, labs use biological safety cabinets or tissue culture hoods that help contain hazardous materials. Also called biosafety cabinets, the equipment has two primary roles – prevent biological agents from affecting personnel and the lab’s environment and safeguard research materials from getting contaminated. Those who deal with biohazards need biosafety cabinets for storage. Some may confuse these with chemical fume hoods or clean benches while they significantly differ.
While biosafety cabinets come with filters, chemical fume hoods don’t have that, as these don’t deal with bio-hazardous materials. The specific fume hood mainly takes care of harmful gases and chemicals. Likewise, clean benches take care of research products. These don’t manage toxic or bio-hazardous agents. Biosafety cabinets, on the other hand, protect samples, people, and the environment from biohazards. The airflow system in the device contains an inflow barrier to block biohazards from getting accidentally released from the cabinet. They also feature downflow air to make the work zone contaminant-free for the sample’s safety. You can visit https://topairsystems.com/ to have an idea of this product.
Selection of biosafety cabinets
Biosafety levels, filtration systems, airflow alarms, work trays, ergonomics, and other factors are critical. Let’s consider them one by one.
Biosafety levels
Biosafety levels help control or separate infectious materials in labs. These devices come in four different levels, from one to four. Level 1 device is best for teaching and educational training settings that don’t deal with pathogenic microorganisms. Level 2 cabinets are suitable for environments with medium-risk agents leading to human ailments. Think of HIV, Toxoplasma, Salmonella, and Hepatitis B. One can use an open bench if the risk of aerosols is lower. Clinical, teaching, and diagnostic labs usually need this type. Since ingestion or exposure to hazardous microorganisms can cause difficulty, one should handle contaminated or sharp objects with utmost care. If the aerosol risk is there, biosafety cabinets are essential even in those areas.
Level 3 cabinets can be typical in various facilities, including production, research, clinical, teaching, diagnostic, and more. These settings need the equipment to handle exotic or indigenous agents that can spread through respiration and be infectious. Coxiella burnetii and Mycobacterium tuberculosis are a few examples of such agents. One should work on these agents in biosafety cabinets or chambers. Choosing a proper ventilation system is also necessary to check hazardous aerosols’ release into the environment.
A facility needs Level 4 cabinets to handle lethal pathogens that can contaminate the area with the help of aerosols and have no treatment for them. Crimean-Congo hemorrhagic fever and Marburg virus are some examples. One can get the infection through aerosols, exposure to droplets, etc. Generally, these types of labs occupy isolated corners with high-end waste management and ventilation systems.
Filtration system
Another essential consideration is the filter in biosafety cabinets. Filters can be of two types – High-Efficiency Particulate Air (HEPA) and Ultra-Low Particulate Air (ULPA). HEPA and ULPA filters enjoy 99.99% efficiency, but their ability to deal with microns differs. HEPA tackles 0.30 microns, whereas the other 0.12 microns.
Airflow Alarm
You come across options like switches, analog displays, and digital microprocessors. Button or switch systems are simple engineering designs that allow you to control lights and blowers. Any difficulty with airflow gets notified through audio and video notification methods. Analog designs measure airflow velocity, indicating any chances of failure. The last option contains alarms, sash status, and airflow values. You can check the cabinet’s status through an LCD monitor and manage different settings.
Work Trays
Cabinet’s surface should remain clean all the time whether there has been spillage or not. One must decontaminate the surface. Since cleanliness is crucial, you also want to focus on this feature. You get two options with work trays – single-piece and multi-piece. Single designs come with a recess that prevents spills from spreading. However, these can be slightly heavy. Another one is lightweight, making it convenient to use. But you may deal with spillage.
Ergonomics
Anything that promotes comfort and productivity should be a priority. When you consider ergonomics, you must focus on the equipment’s control panel, which should be easily accessible, regardless of its location. The center position can be good. You must also check whether you can access the unit, whether sitting down or standing up. Another area is noise. Biosafety cabinets’ noise levels should remain within 67 dBA to avoid causing any disruptions. Let’s also consider lighting. The cabinet should be well-lit without being glaring. Else, people will find it difficult to focus on their work. Also, the UV light’s angle must be proper to protect your eyes from irritation.
Windows
Motorized sash, manual sash, and hinged windows are the standard options. Each mechanism is unique, but you must select something based on your lab’s needs. Motorized windows are an enhanced version of manual sash windows in their operability. You find one or two buttons to control the window opening or closing. During work with UV light, the window should remain closed. The hinged window models have a tiny aperture opening because it’s a fixed design. When using UV light, the person should use a separate front cover on the aperture. Users should be careful about the window opening height when working with manual sash windows.
The biosafety cabinet sash can be laminated or tempered glass material because of its ability to absorb UV rays and stay intact even when it shatters due to contact with a sharp object. Furthermore, windows can be sloped/ angled or vertical models. Modern designs usually have an angled front to offer high visibility while reducing challenges like reflections and glares.
Remember, this equipment handles pathogenic samples or works requiring a sterile environment. With its inflow air barrier, the cabinet keeps the operator safe from biohazards. The downflow air creates another safety net for the samples inside. The efficient use of biosafety cabinets usually depends on the operators. That’s why it’s necessary to have trained people for these projects.