# Proper Use of a Biosafety Cabinet A biosafety cabinet (BSC) is a ventilated, partly enclosed workspace that protects the operator from aerosols generated during work with infectious material, protects the specimen from contamination by room air, and protects the laboratory and community by exhausting or filtering contaminated air. Correct technique at the cabinet is one of the highest-yield safety behaviors in a diagnostic microbiology laboratory. Poor technique can turn a perfectly engineered enclosure into a source of exposure and contaminated cultures. Hands-on time for the standard pre-work routine (PPE, wipe-down, loading, purge) is 10 to 15 minutes. A single working session inside the cabinet typically runs from 30 minutes to several hours depending on the protocol. Long-term responsibilities, including annual certification and periodic decontamination, recur at intervals set by your institution and the certification standard in effect. This guide covers the principle behind cabinet protection, a biosafety risk assessment framework for choosing the right cabinet, the full step-by-step work procedure with the reason behind each critical step, the controls and airflow checks that tell you the cabinet is actually protecting you, a troubleshooting table, common mistakes, variations, and a short training section. ## Principle: How a Biosafety Cabinet Protects Three Things at Once A BSC uses a fan, a high-efficiency particulate air (HEPA) filter, and a carefully balanced airflow pattern to achieve three simultaneous protections, often called the product, person, and environment triad. - **Product protection.** HEPA-filtered air is blown down through the work space in a laminar sheet, sweeping particles away from your materials so that cultures and plates are not contaminated by dust or room organisms. - **Person protection.** Room air is drawn continuously through the front opening of the cabinet, so any aerosols you generate are pulled inward and downward, away from your face, into the filtration system rather than out into the room. This inward curtain is the single most important protective feature. Breaking or disturbing that air curtain is the root cause of most cabinet-related exposures. - **Environmental protection.** Exhaust air passes through HEPA filtration before it is recirculated into the room or ducted outdoors, depending on the cabinet type. Cabinets are classified by design and containment performance. A Class I cabinet draws unrecirculated room air across the work surface and exhausts it through a HEPA filter, providing person and environmental protection but no product protection. Class II cabinets, the workhorses of [clinical microbiology](/knowledge/diagnostics/microbiology/clinical-microbiology-from-specimen-collection-to-pathogen-identification), use a vertical laminar downflow of HEPA-filtered air mixed with an inward air curtain, providing all three protections. Class II cabinets are subdivided into Types A1, A2, B1, and B2, which differ mainly in the proportion of air recirculated versus exhausted and whether exhaust is ducted to the outside. Type A2 cabinets recirculate most of the air internally and are suitable for work with infectious agents requiring [Biosafety Level](/knowledge/diagnostics/emerging-tech/biosafety-levels-1-4-a-comparative-framework-for-diagnostic-laboratory-design) 2 (BSL-2) practices. Type B2 cabinets recirculate nothing and are total-exhaust units suited for work involving volatile chemicals in addition to biological hazards. Class III cabinets are fully enclosed, gas-tight, glove-lined units for the highest-risk agents. The choice among these types is not arbitrary. It follows from the agent, the procedure, and the assessed risk, which is why a documented biosafety risk assessment must come before cabinet selection and use [1], [2]. The World Health Organization emphasizes that validated cabinets, matched to the work, are part of the baseline quality and safety expectation for diagnostic and research laboratories [2]. ## Start With a Biosafety Risk Assessment, Not With the Cabinet Cabinet selection and work practices should flow from a structured risk assessment that considers at least five elements: 1. **The agent.** Route of transmission, infectious dose, known laboratory-acquired infections, and severity of disease. 2. **The procedure.** Whether the activity generates aerosols, splashes, or high concentrations of the agent. Opening tubes, vortexing, centrifugation outside sealed rotors, and sonication all raise risk. 3. **The volume and concentration.** Large-volume cultures concentrate risk in ways that a smear or an identification test does not. 4. **The people.** Training, vaccination status, immunocompromise, and other predisposing risk factors among staff. 5. **The facility and resources.** What containment and equipment actually exist in your laboratory. The last element deserves emphasis. Risk assessment is situational. A published field study of Burkholderia pseudomallei, a Tier 1 select agent normally handled in a Class II cabinet within a BSL-3 facility, found no serologic evidence of infection among 30 laboratory scientists who handled isolates on 1,267 occasions outside a biosafety cabinet, and air sampling during 78 handling events including plate opening and oxidase testing detected no aerosolization of the organism. The authors still concluded that each laboratory must undertake its own assessment covering endemicity, available containment resources, the nature of the routine work, and predisposing risk factors in staff, along with region-specific guidance [3]. The lesson generalizes to every agent. Risk assessments balance documented hazards against real operational constraints, and they must be documented, reviewed, and owned by someone. Respiratory pathogens illustrate why the assessment matters. A systematic review of the evidence base for [avian influenza](/knowledge/bacteria/avian-bacteria/avian-influenza-new-zealand-kerala-outbreaks-jessamine-county-updates) virus and Mycobacterium tuberculosis identified significant gaps, including the lack of definitive data on M. tuberculosis sample aerosolization during diagnostic procedures, and noted that existing guidance on which procedures require a biosafety cabinet for M. tuberculosis requires clarification [4]. Where the evidence is incomplete, laboratories should default to the more conservative practice: perform manipulations with the potential to create aerosols inside a properly functioning Class II cabinet. One practical corollary of the risk assessment is route matching. If the agent is primarily an inhalation hazard, procedures that could aerosolize it belong in a BSC. If the agent is a bloodborne pathogen handled mainly in closed tubes, the risk assessment may support safe handling in some cases with gloves, face protection, and standard precautions rather than full cabinet work, but any manipulation that opens a container, aliquots, or centrifuges unsealed material belongs in the cabinet. ## Materials and Equipment | Item | Working concentration or specification | Purpose | |--|--|--| | Certified Class II BSC (correct type for your work) | Certified within the last 12 months, airflow alarm functional | Primary containment | | Low- or intermediate-level disinfectant | 70% ethanol or 70% isopropyl alcohol in water, or an EPA-registered hospital disinfectant | Surface decontamination before and after work | | Sodium hypochlorite solution (household bleach) | 0.5% to 1% diluted fresh daily, followed by a water or 70% alcohol wipe | Spill response and periodic decontamination of bleach-compatible surfaces | | Disposable absorbent bench liner | Plastic-backed pad, changed per session | Absorbs splashes, reduces droplet spread | | Sharps and biohazard waste containers | Placed inside the cabinet for the session | Keeps sharps disposal within containment, avoids repeated arm crossings | | PPE | Laboratory coat or gown, disposable gloves, eye and face protection as risk assessment requires | Personal barrier layer | | Pipetting devices | Mechanical or electronic pipettors with filtered tips | Eliminates mouth pipetting (obsolete) and reduces aerosol generation | | Biological spill kit | Absorbent material, disinfectant, sharps tongs, biohazard bags | Immediate spill response | | Certified autoclave or validated waste treatment | Per institutional protocol | Decontamination of waste leaving the cabinet | **Safety note.** Alcohol-based disinfectants burn readily in the oxygen-enriched, airflow-active environment inside a cabinet. Use small quantities, cap containers when not in use, and never use open flames. Flammable-liquid vapors are also a problem in recirculating cabinets, as discussed under Variations. ## Proper Use of a Biosafety Cabinet, Step by Step ![Five steps from verifying certification to wiping down, loading materials and letting airflow settle before work.](/article-images/illustrations/biosafety-cabinet-proper-use-pre-work-purge.webp) The following procedure reflects consensus work practice for a Class II cabinet. The reason column is the part most often skipped in training, and it is the part that prevents both exposures and contaminated cultures. 1. **Verify certification status before you sit down.** Check the certification sticker date and confirm the cabinet passed its most recent test. A cabinet out of certification is not a cabinet. Annual certification and re-testing after any move, filter change, or repair are the standard expectation. *Reason:* Certification verifies that inward velocity, downflow, and containment performance still meet specifications. Performance degrades silently with filter loading, motor wear, and facility airflow changes. 2. **Confirm the airflow alarm and indicator are normal.** Turn on the cabinet, blower and lights, and check the airflow indicator or differential pressure gauge against the normal reading noted on the cabinet. Wait 3 to 5 minutes to purge the work space and let airflow stabilize before touching anything inside. *Reason:* The purge flushes contaminated or stagnant air from the work zone and re-establishes the air curtain. Working immediately after power-up means working in unstable airflow. 3. **Put on PPE and wash your hands.** Laboratory coat or gown, gloves appropriate to the risk assessment, and eye or face protection where the risk assessment calls for it. Wash hands before gloving. *Reason:* Training in personal protection and aseptic technique at the cabinet measurably reduces the chance of contaminating the surrounding area [5]. Hand hygiene before donning gloves protects the product and your own skin. 4. **Wipe down every surface you will touch.** Disinfect the interior work surface, back and side walls, sash interior, and the drain valve or catch tray if present, using 70% ethanol or an appropriate disinfectant. Allow contact time. *Reason:* The cabinet protects your product from room contamination only if the work zone itself starts clean. Bring the same hygiene discipline you would apply to a surgical field. 5. **Load your materials correctly and let the airflow restabilize.** Place pipettes, culture media, tubes, waste container, and the day's worksheet inside, arranged so that a clean-to-dirty flow runs from left to right or front to back, with materials kept at least several inches inside the front sash and clear of the front and rear grille openings. Never place anything on the grille openings themselves. Then wait another 2 to 3 minutes. *Reason:* Loading is the step most likely to destroy the air curtain. Boxes and racks sitting across the grille deflect the inflow and can allow aerosols to escape toward your face. Restabilizing the airflow after loading restores the protective curtain before you work. 6. **Work at least 6 inches (15 cm) behind the sash opening.** Perform all manipulations deep in the cabinet, never at the front edge. *Reason:* The inward air curtain is most stable a few inches behind the opening. Work at the very edge places your hands in the zone where the inflow and downflow meet, where turbulence can push aerosols back out. 7. **Minimize arm movement and traffic behind you.** Enter and withdraw your arms straight and slowly. Announce "my cabinet" before someone approaches, and ask others to avoid walking past while you work. *Reason:* Rapid arm movement and nearby foot traffic generate eddies that can pull contaminated air out of the front opening. Multiple operators at adjacent cabinets, or people moving behind you, are a documented source of failed containment tests. 8. **Keep the sash at the marked working height.** Do not raise the sash beyond its marked level, and do not work with the sash partially closed against the airflow design. *Reason:* The cabinet's airflow balance was certified at a specific sash height. Changing it changes the inflow velocity and can invalidate containment. 9. **Do not use open flames.** Use an electric or bead-sterilizing device, or better, rely on the sterile downflow and single-use sterile consumables. *Reason:* Flame heat creates rising convection currents that disrupt the laminar downflow, and the flame is a fire hazard in an oxygen-rich, airflow-active space full of alcohol vapors. 10. **Handle liquids to minimize aerosols.** Discharge pipettes down the inside of the receiving vessel, below the liquid surface where possible. Avoid vigorous vortexing or shaking inside the cabinet. Open tubes slowly. When a procedure will generate significant aerosols, keep the tube held within the downflow zone rather than lifting it toward the sash. *Reason:* The cabinet is designed to capture aerosols that drift downward into the inflow. It cannot protect you from a jet of aerosol directed straight out the front. 11. **Keep waste inside the cabinet.** Discard pipettes into a container within the cabinet and place contaminated materials into a biohazard bag held inside until the end of the session. *Reason:* Carrying open contaminated items in and out multiplies arm crossings through the air curtain and spreads contamination beyond the work zone. 12. **Close and decontaminate everything before removal.** Cap or cover all open containers, then wipe every item with disinfectant before it crosses the plane of the sash. Discard the bench liner into biohazard waste. 13. **Wipe down the interior again at the end of the session.** Disinfect all interior surfaces, working from the back toward the front, and run the blower for several minutes to purge before switching off, or leave the cabinet running if your institution's practice is continuous operation. 14. **Decontaminate your hands.** Remove gloves, wash hands, and document the session per local practice. 15. **Report any anomaly immediately.** If the alarm sounds, the airflow indicator reads abnormally, or you notice unusual noise or vibration, stop work, cover or seal your materials, and notify the biosafety officer. *Reason:* An alarm during work means the containment assumption has failed. Continuing is how laboratory-acquired infections happen. **Safety note on disinfectants.** Bleach is corrosive to stainless steel. If you use it for spills, follow with a water or alcohol wipe on cabinet surfaces and never leave bleach standing in the drain pan. ## Controls, Expected Results, and How to Read Them Think of the cabinet as an instrument that must be "run" before and during every session, with its own set of controls. ### Pre-use controls - **Certification sticker.** Current within 12 months, or per your institution's shorter interval. - **Airflow alarm check.** Alarms that do not sound, or indicators stuck at a fixed number, are red flags. Report them and do not use the cabinet. - **Visual airflow check.** A tissue strip held at the sash opening should be drawn inward and down, not fluttered outward. Many operators also use the smoke pencil or visualized smoke pattern during certification. A simple check: hold a strip of tissue near the front edge, release it, and it should drift into the cabinet. ### Certification-level controls (performed by the certifier) Field certification against the applicable standard typically includes measured inward airflow velocity, downflow velocity, airflow smoke pattern tests for containment integrity, and a leak test of the HEPA filter. These tests verify that the cabinet performs as designed. When your cabinet is recertified, ask for the airflow values and compare them with previous years. A slow drift in velocity often predicts filter loading or motor problems months before an alarm. ### What good looks like during use - No detectable odor or airflow sensation at your face. - Culture media incubated after cabinet work show no more contamination than expected for the medium type. - Plates and tubes placed in the cabinet overnight under stable airflow remain clean. - The airflow indicator holds steady throughout the session. ### What bad looks like - Condensation or dust settling on the interior of the sash glass at the level of your working hands, indicating outflow of contaminated air. - Turbulence you can feel at the sash when a person walks past. - Contamination appearing in your sterility controls or unopened media plates. - The airflow alarm triggering while you work. Any of these means stop work, contain your materials, and get the cabinet checked before the next session. ## Troubleshooting Table | Symptom | Likely cause | Fix | |--|--|--| | Airflow alarm during work | Sash above marked height, blocked grille, or facility airflow change | Lower sash, clear obstructions, stop work and call for service if it recurs | | Airflow reads low on the indicator | Filter loading, motor degradation, or prefilter clogged | Report to certification service. Do not attempt filter work yourself | | Visible outward air movement at sash edge | Operator or nearby person moving too fast, cabinet located near door or HVAC diffuser | Slow all movements, restrict traffic, request airflow balancing of the room | | Contaminated sterility controls or unopened plates | Downflow turbulence from overloaded work zone, or interior surface contamination | Reduce load, redistribute materials, review wipe-down technique, recertify | | Persistent odor at the operator position | Reverse airflow at the opening, or chemical use inappropriate for a recirculating cabinet | Stop work, verify airflow, remove volatile chemicals from cabinet use | | Splatter visible on interior walls or sash | Liquid handling technique, overfilled loops or pipettes | Discharge below liquid surfaces, use shorter filling, add absorbent liner | | Fan running but no inward flow at the opening | Blocked prefilter or supply, or exhaust duct obstruction | Remove from service, call certifier or service technician | | Glove or sash damage discovered mid-session | Wear and tear | Stop work, seal materials inside if safe to do so, decontaminate, repair before next use | ## Common Mistakes and Limitations These are the errors that recur most often in laboratory observations and proficiency reviews, phrased as what to do differently. - **Working at the front edge.** The most common single error. Everything you do should happen deep in the cabinet. If your elbows rest on the sash sill while your hands are at the edge, your work zone is wrong. - **Overloading the cabinet.** Packing racks, a rigid waste box, and an unopened box of pipettes into every square inch destroys the airflow pattern. Load only what the session needs and keep grilles clear. - **Treating the cabinet as a fume hood.** Class II Type A cabinets recirculate most of their air through the work zone. Volatile toxic chemicals and radioactive materials generally do not belong in them unless the cabinet is specifically designed and ducted for that use. The distinction between BSC types exists precisely because the wrong match between cabinet and hazard is dangerous [2]. - **Skipping the purge after loading.** Placing a rack and immediately plunging in puts your hands in unstable air. - **Open flames.** A Bunsen burner inside a Class II cabinet disrupts downflow and creates a fire hazard. This practice persists in some teaching laboratories and should end. - **UV lamps as a substitute for wiping.** Ultraviolet germicidal irradiance has limited penetration, is blocked by shadows and organic soil, and does not reach surfaces behind equipment. Chemical wipe-down remains the primary decontamination method. Where UV lamps are used, there are additional considerations. In one controlled evaluation, a 15-minute UV-C exposure inside a Class II cabinet did not affect the stability of 444 antidoping analytes spiked into urine samples held in their original containers, which addressed a sample-integrity concern in that setting [6]. The broader point for microbiology is that UV can be an adjunct for reducing nucleic acid and microbial burden on exposed surfaces, but it never replaces physical cleaning. - **Ignoring the certification date.** An expired sticker means the containment claim is unsupported. In Ethiopia's Debre Berhan town governmental hospital laboratories, only 18.5% of surveyed professionals had access to biological safety cabinets, and biosafety training adherence was similarly low at 18.5%, illustrating how equipment and training gaps travel together in real facilities [7]. If your own laboratory has an expired cabinet, escalate rather than improvise. - **Assuming the cabinet protects against everything.** A BSC is a primary barrier for aerosols and splashes of infectious material. It is not a substitute for sealed rotors and safety cups for centrifugation of high-risk specimens, for sharps discipline, or for vaccination and post-exposure planning. - **Wearing contaminated gloves outside the cabinet between steps.** Constant arm crossing with contaminated gloves spreads material to the sash, the room, and your face. Stage materials and keep waste inside. - **Relying on the cabinet to fix a bad procedure.** A cabinet captures aerosols that reach the inflow. It cannot compensate for a technique that sprays suspension across the sash glass. **Limitations of the method.** Even the best cabinet work practice has boundaries. Cabinet protection depends on certification status, facility airflow, and operator behavior simultaneously. The evidence base for some agent- and procedure-specific recommendations remains incomplete, and individual risk assessments, institutional policy, and your biosafety officer's direction govern what you may do in your own laboratory. Individual cases and unusual agents always require consultation with your institution's biosafety professional rather than a general article. ## Variations ### Choosing the cabinet type for the work ![Decision path from the agent and procedure to a Class I, Class II Type A2, Type B2 or Class III cabinet.](/article-images/illustrations/biosafety-cabinet-proper-use-cabinet-type-choice.webp) Type A2 cabinets suit most routine clinical bacteriology, mycobacteriology at BSL-2 within a sealed containment suite where local policy permits, virology, and molecular workflows that do not involve volatile chemicals. Type B1 and B2 cabinets handle work with hazardous chemical components because they duct all or most air outside. Class I cabinets remain useful for aerosol-generating equipment such as centrifuges or blenders that can be enclosed within them. The confusion that historically surrounded cabinet selection, installation, testing, and use among microbiologists was addressed directly in the standard reference literature on the topic, which remains a good orientation for laboratory managers planning new facilities [1]. ### Work with high-risk respiratory agents For agents such as M. tuberculosis, avian influenza virus, and other respiratory pathogens, the risk assessment drives cabinet selection and procedure restrictions. Where published guidance on specific procedures is ambiguous, laboratories should err toward performing aerosol-generating steps in a certified Class II cabinet and should track new evidence as it emerges [4]. Diagnostic cultures and liquid suspensions of these agents demand the full step-by-step discipline described above, plus institutional respiratory protection requirements. ### UV-C as an adjunct Where a cabinet is equipped with a germicidal UV lamp, typical practice is to run the lamp after chemical wipe-down with the sash closed, for a defined interval such as 15 minutes, and to validate that the lamp does not compromise the materials you work with. The urine-sample study cited above demonstrated that common small molecules, metabolites, and peptides were stable after a 15-minute UV-C exposure in a BSC, but analytical chemistry requirements differ from microbiology requirements, so validate for your own materials [6]. ### Aerosol-generating instruments connected to cabinets Some instruments, notably cell sorters handling potentially infectious samples, use an aerosol evacuation system rather than a conventional BSC. Because such systems are frequently not retested after installation, a user verification protocol exists in which aerosols are generated with 1-micron fluorescent beads during a simulated stream disruption, sampled just outside the containment area with a disposable impactor-style cassette, and examined to confirm containment before infectious samples are run [8]. The general principle transfers to any laboratory with aerosol-generating equipment: containment that has not been verified is containment you cannot assume. ### Site of use in outbreak and field settings Mobile and outbreak-response laboratories frequently operate in spaces with unstable room airflow. In these settings, cabinets should be placed away from doors, windows, and supply diffusers, and certified on-site after every relocation before use. Post-move recertification is not optional. ## Storage, Maintenance, and Stability Notes - **Certification interval.** Annual certification at minimum, plus recertification after relocation, filter replacement, or any repair affecting airflow. - **Between sessions.** Follow your institution's policy on continuous versus intermittent operation. Where cabinets are switched off, allow the 3-to-5-minute stabilization purge before every session, without exception. - **Interior decontamination.** Wipe down at the start and end of each session. Schedule periodic deeper cleaning, including drain pans and under work surfaces, and a formal decontamination, most commonly with paraformaldehyde gas by a qualified service provider, before filter changes, internal repairs, or cabinet relocation. - **Prefilters.** Clean or replace room-facing prefilters per the manufacturer's schedule. A loaded prefilter starves the blower and degrades containment. - **Disinfectant stability.** Prepare bleach dilutions fresh daily. Alcohol solutions lose concentration through evaporation, so date and discard opened bottles per your laboratory's reagent dating policy. - **UV lamps.** Replace on the manufacturer's schedule, because germicidal output declines with hours well before the lamp stops lighting. Track lamp hours if the manufacturer specifies a limit. ## Microbiology Biosafety Training: The Human Control A certified cabinet protects only the operator who uses it correctly. Structured training in cabinet work, covering aseptic procedure, hand posture, personal protection, and movement discipline, directly reduces contamination of the surrounding laboratory environment and is the core of practical biosafety competence in clinical microbiology [5]. Effective microbiology biosafety training has three components: 1. **Initial competency.** Didactic instruction plus supervised bench work with a documented competency assessment, including observed work inside the cabinet and response to a simulated alarm or spill. 2. **Refresher cycles.** Annual or biennial review, tied to the certification calendar and to incident reports. 3. **Correction loops.** When troubleshooting reveals contamination or airflow failures attributable to technique, retrain the specific behavior rather than repeating general lectures. The gap between policy and practice is measurable. In the Debre Berhan cross-sectional survey of 81 clinical laboratory professionals, compliance with basic work habits such as mechanical pipette use (95.1%) and handwashing after biohazard handling (96.3%) was high, while protective barrier use (61.7%), biosafety training participation (18.5%), and emergency preparedness (34.6%) lagged far behind, and experience and training were associated with better adherence [7]. Laboratories planning to strengthen their programs should target training access and emergency preparedness first, because those are the variables that correspond to cabinet competence. ## Frequently Asked Questions ### What is the difference between a biosafety cabinet and a laminar flow hood? A biosafety cabinet pulls air inward through the front opening to protect the operator, while a laminar flow hood blows filtered air outward toward the operator to protect only the product. A clean bench is appropriate for preparing sterile reagents with no hazardous material, and never for infectious agents. ### How often does a biosafety cabinet need to be certified? At least annually, and also after any relocation, HEPA filter change, or repair that could affect airflow. Check the certification sticker before every use and do not work in an out-of-certification cabinet. ### Can I use a Bunsen burner inside a biosafety cabinet? No. The flame disrupts the laminar downflow and creates a fire hazard in the alcohol-rich, airflow-active environment. Use electric bead sterilizers or sterile single-use consumables instead. ### How long should the cabinet run before I start work? Turn it on, let it purge for 3 to 5 minutes after startup, and allow another 2 to 3 minutes after loading your materials so the airflow restabilizes before your hands enter the work zone. ### What disinfectant should I use to wipe down the cabinet? Seventy percent ethanol or isopropyl alcohol is standard for routine wipe-downs. Use freshly diluted bleach for spill cleanup, followed by a water or alcohol wipe to protect the stainless steel. ### Does the UV lamp inside the cabinet replace chemical disinfection? No. UV light is blocked by shadows and organic soil and reaches only directly exposed surfaces. Chemical wipe-down remains the primary decontamination method, with UV as an optional adjunct. ### Can I work with radioactive materials or volatile chemicals in a biosafety cabinet? Standard Class II Type A2 cabinets recirculate most of their air internally and are not designed for volatile toxic chemicals or radioactive material. Total-exhaust cabinets such as Type B2, installed and ducted for that purpose, are the appropriate choice where the risk assessment supports chemical work. ### What class of cabinet do I need for routine clinical bacteriology? A certified Class II cabinet, most commonly Type A2, is the standard choice for routine BSL-2 diagnostic bacteriology. Confirm the specific type against your laboratory's biosafety risk assessment for the agents and procedures you actually perform. ## Sources 1. [Microbiological safety cabinets: selection, installation, testing and use.](https://pubmed.ncbi.nlm.nih.gov/11204866/) 2. [Selection and application of biological safety cabinets in diagnostic and research laboratories with special emphasis on COVID-19.](https://pubmed.ncbi.nlm.nih.gov/34470433/) 3. [Laboratory Safety: Handling Burkholderia pseudomallei Isolates without a Biosafety Cabinet.](https://pubmed.ncbi.nlm.nih.gov/33910967/) 4. [The Biosafety Research Road Map: The Search for Evidence to Support Practices in the Laboratory-Zoonotic Avian Influenza and Mycobacterium tuberculosis.](https://pubmed.ncbi.nlm.nih.gov/37736423/) 5. [The Role of the Biosafety Cabinet in Preventing Infection in the Clinical Laboratory.](https://pubmed.ncbi.nlm.nih.gov/38288229/) 6. [Biosafety Level 2 cabinet UV-C light exposure of sports antidoping human urine samples does not affect the stability of selected prohibited substances.](https://pubmed.ncbi.nlm.nih.gov/33119942/) 7. [Biosafety Management Practices Among Clinical Laboratory Professionals in Debre Berhan Town Governmental Hospitals, Ethiopia: A Cross-Sectional Study.](https://pubmed.ncbi.nlm.nih.gov/39872910/) 8. [Verifying Proper Function of the Aerosol Evacuation System Prior to Sorting Potentially Infectious Samples.](https://pubmed.ncbi.nlm.nih.gov/40116472/)