A biological safety cabinet (BSC) is a primary engineering control used to protect personnel against biohazardous or infectious agents and to help maintain quality control of the material being worked with as it filters both the inflow and exhaust air. It is sometimes referred to as a laminar flow or tissue culture hood. Show
These filtered cabinets are primarily designed to protect against exposure to particulates or aerosols. A portion of the air in most BSCs is recirculated back into the lab through its exhaust HEPA filter. This purifies the air of potentially infectious aerosols, animal dander, or both but does not reduce exposure to chemicals. All procedures should be performed in a manner that reduces the generation of aerosolized material and prevents spills. Operations such as centrifugation, vortexing, sonication, and opening containers of infectious materials whose internal pressure may be different from the ambient pressure are known aerosol-generating procedures. These procedures should be conducted inside the BSC or additional measures must be available to mitigate the safety concern. Contact the EHS representative assigned to your BSC or the EHS main line at (734) 647-1143 for guidance regarding proper BSC:
Standard Operating Procedures, Guidelines, and ManualsThe following documents may be required for your research operation, depending on what type of research you are performing, the potential hazards you and your staff will be exposed to, and the engineering controls you are implementing. Some of these documents are in a downloadable “Word” format so that you can print them for your operation as is, or download and modify them to meet your unique needs. When you click the link it will automatically go to the download file.
EHS Engineering Controls of Standard Care
Lab Director ResponsibilitiesLab directors (faculty/lab managers/supervisors) must:
Lab Personnel ResponsibilitiesLab personnel must:
CertificationBiological safety cabinets must be inspected and certified by EHS:
If your BSC has not been certified within the last year, or if you have any questions regarding BSCs, call EHS at (734) 647-1143. Skip to content Skip to main navigation Report an accessibility issue This module covers the laboratory practices and procedures associated with Biosafety Levels 1 & 2. To summarize: Biosafety Level-1 represents a basic level of containment that relies on standard microbiological practices with no
special primary or secondary barriers recommended, other than a sink for hand washing. BSL-1 practices, safety equipment, and facility design and construction are appropriate for most undergraduate and secondary educational training and teaching laboratories, and for other laboratories in which work is done with defined and well-characterized strains of viable microorganisms not known to consistently cause disease in healthy adult humans or negatively impact the environment. However, many agents
not ordinarily associated with disease processes in humans can be opportunistic pathogens and may cause infection in the young, the aged, and immunodeficient or immunosuppressed individuals. Additionally, vaccine strains that have undergone multiple in vivo passages should not be considered avirulent. Biosafety Level-2 containment and safety practices are suitable for work with a broad spectrum of indigenous moderate-risk agents that typically cause mild-to-moderate human disease. Additionally, BSL-2 is usually the default biosafety level when working with diagnostic specimens from humans and/or animals. BSL-1 vs. BSL-2 considerations are summarized below. With elevated risk, comes elevated containment. The foundation of each biosafety level is
standard microbiological practices (SMP). BSL-1 labs employ SMP as the baseline criteria for biological safety & containment. Subsequent BSLs build upon SMP with more specialized design, equipment, and practices. 3.1.2 SMP and BSL-2 PracticesOther SMP to be used in laboratories handling biological materials include:
Biosafety Level 2 practices (BSL-2) consist of SMP plus:
3.2 HAZARD COMMUNICATION3.2.1 PlacardsBSL-2 (& BSL-3) labs can be easily differentiated from BSL-1 labs in that the outer doors of areas where biological hazards are manipulated feature cautionary placards. The Biosafety Office-approved placard is exampled here. Placards are available by contacting the Biosafety Office. At UTK, the universal biohazard symbol and the word “BIOHAZARD” are used to indicate higher risk areas where there is a risk to human health. Therefore, BSL-2 door placards feature the universal biohazard symbol which alerts lab workers, visitors, maintenance & housekeeping personnel, vendors, and others who may need to enter the laboratory. Placards also communicate entry considerations, e.g.:
3.2.2 Hazard Communication - Equipment LabelsEquipment used to process or store biohazards that may impact human health must be labeled with the universal biohazard symbol. For example, hoods, freezers, incubators, and centrifuges, etc. are labeled if they are used with risk group 2 (RG2) agents or higher. Also, transport containers and biohazard waste containers must display a biohazard label on the outermost part. 3.3 HANDWASHINGOne of the simplest measures you can take to protect yourself (and others) inside and outside of the laboratory is washing your hands. This simple procedure has been thoroughly demonstrated to be the primary means of infection and contamination control in laboratory and clinical settings. In other words, hand washing is extremely important in preventing lab acquired infections (LAIs) and minimizing the spread of infectious materials. Upon entering the lab, you should familiarize yourself with critical lab infrastructure and where it is located: fire alarms/extinguishers, emergency shower, first-aid kits, emergency eyewash stations and hand washing sinks. 3.3.1 Handwashing ProcedureHands must be washed:
Procedure:
Hand Hygiene – A word about hand sanitizers: In case of limited access to soap and water (e.g. field procedures), waterless hand sanitizers may be used as a temporary means of reducing contamination until a source of running water and soap can be reached. However, because of the variety of products available and organisms used in UT labs, the Biosafety Office cannot adequately validate waterless hand sanitizers for efficacy in all cases. Therefore, these products are NOT a replacement for hand washing with soap and water and should not be used as such. When using a waterless sanitizer:
3.4 EMERGENCY EYEWASHESEyewashes are required for labs operating a BSL-2, though they are often found in BSL-1 labs as well. Eyewashes must be maintained in good working order and flushed according to the EHS requirements for general lab hygiene, generally weekly. The eyewash is in place for your protection. Weekly flushes keep sediment and bacteria from accumulating in the lines which could potentially cause harm to your eyes in case of emergency use.
3.5 ELIMINATE ROUTES OF ENTRY3.5.1 Laboratory Clothing3.5.2 Personal Protective EquipmentWhat is personal protective equipment? Personal protective equipment, commonly referred to as “PPE”, is equipment worn to minimize exposure to hazards that cause serious workplace injuries and illnesses. These injuries and illnesses may result from contact with biological, chemical, radiological, physical, electrical, mechanical, or other workplace hazards. Personal protective equipment may include items such as gloves, safety glasses, chemical splash goggles, lab coats, and respiratory protection. What can be done to ensure proper use of personal protective equipment? Employers are also required to train each worker required to use personal protective equipment to know:
3.5.2.1 Personal Protective Equipment - HandsGloves Gloves must be:
Donning & Doffing Gloves 3.5.2.2 Personal Protective Equipment - BodyLab coats Protective lab coats are recommended to prevent contamination of personal clothing at BSL-1. At BSL-2, they must be worn when working with hazardous materials. Lab coats must be:
3.5.2.3 Personal Protective Equipment - EyesEye Protection Wear protective eye wear when conducting procedures that have the potential to create splashes of microorganisms or other hazardous materials. Eye protection must be:
3.5.2.4 Personal Protective Equipment - FaceFace Protection Face protection must be:
3.5.2.5 Personal Protective Equipment - Respiratory ProtectionRespiratory Protection 3.6 FOMITE TRANSMISSIONBesides direct contact with contaminated fluids, infectious agents may also be transmitted by fomites. Fomites are inanimate objects or materials that are likely to harbor and spread infectious agents through contact. Examples include: equipment, utensils, doorknobs, keyboards, furniture, PPE, and cell phones. Practices to minimize fomite transmission are outlined below: 3.7 AEROSOL RISKIn 2012, the CDC estimated approximately 80% of laboratory acquired infections are caused by aerosols of pathogenic microorganisms. Laboratory personnel who work with agents infectious to humans must ask themselves: 1) Am I working with concentrated stocks? 2) Will my procedures concentrate the risk group 2 pathogens (e.g., high-speed centrifugation)? 3) Does my procedure generate aerosols? Aerosols are solid or liquid particles suspended in the air (1-100 µm). The fate of these particles is determined by relative size:
Common laboratory procedures that may produce aerosols include:
Devices that have the potential to create aerosols: Aerosol droplets are formed with virtually any activity that disrupts the surface tension of a liquid or applies mechanical force to a solid. As liquid particles bearing infectious agents may remain in the air for extended periods, it is important to consider methods of aerosol control. Using a combination of the appropriate safety equipment and safe procedures is the primary method to minimize the creation of and exposure to aerosols. Lab safety equipment to protect personnel from aerosols
Safe work practices for centrifugation of biohazards
Safe work practices for blending, sonicating, grinding, and lyophilizing of biohazards
Safe work practices for pipetting of biohazards
Other safety precautions
3.8 BIOLOGICAL SAFETY CABINETS (BSC)BSCs use HEPA (high-efficiency particulate air) filters to filter infectious particles from an airstream. BSCs may be used at BSL-1 to maintain an environment of sterility that is not achieved on the open bench. At BSL-2, the BSC is relied upon to protect the worker and the environment from procedures that are likely to generate aerosols. However, BSCs are only effective if used properly. This requires an understanding of how they function as well as proper technique. NOTE: BSCs remove particles, not vapors. Volatile hazardous chemicals are not to be used in a BSC unless approved by the Biosafety Office. The Biosafety Office requires that BSCs used for BSL-2 containment be certified:
The certification verifies HEPA filter efficiency and calibration of the airflow that provided that protective inward airflow at the face of the cabinet. Certification is performed by a contracted field certifier in accordance with prescribed parameters. Once certified, the BSC will be tagged by the contractor as illustrated here. While biosafety cabinets are not required for worker protection in BSL-1 containment, if they are used, annual certification will help ensure that the intention of use is met, regardless of the operating biosafety level. If your BSC is due for certification, or if you need a list of approved field certifiers, contact the Biosafety Office at 974-1938.
For additional resources on the care and use of BSCs, see:
The Laminar Flow Bench:
The Chemical Fume Hood:
3.9 CENTRIFUGESThe centrifuge is a commonly used tool in laboratory research. It uses centrifugal force to separate substances in liquid or solid media according to particle size and density differences. Centrifugation may present two serious hazards: mechanical failure and dispersion of aerosols. Therefore, training on how to use the centrifuge properly and safely is essential for all new employees as part of Lab-Specific Training. 3.9.1.1 Before Centrifugation
3.9.1.2 During centrifugation
3.9.1.3 After centrifugation
3.9.1.4 Centrifuging Infectious Materials or Human Samples Follow the safety procedures above, plus:
3.9.2 Centrifuge Emergency Procedures3.9.2.1 Emergency Situations The following events are considered an emergency:
3.9.2.2 Emergency Procedures For emergencies with RG2 organisms or hazardous materials
3.10 DECONTAMINATION AND DISINFECTIONThe university requires that all individuals that work in a laboratory are adequately informed about the chemical, physical, and health hazards present in the laboratory, the known risks, and what to do if an accident occurs. Proper approaches to disinfection and decontamination are important for the protection of lab personnel and for the prevention of environmental release of organisms. Removal of infectious agents by surface cleaning is a critical component of biological safety in the lab. While the immediate work space is an obvious area requiring regular decontamination procedures, there remain other critical items which might not be as apparent. These can include:
When selecting a disinfectant, it is important to understand the compound that you are using:
Currently, there are a wide variety of disinfectant options available. The products generally fall into the following categories (listed from low-level to high-level disinfectants):
3.11 SHARPS MANAGEMENTIn the lab, a sharp refers to any object that is contaminated with a biologically hazardous agent and is sharp enough to puncture the skin without excessive applied pressure of force. While needles and scalpels could be considered the most apparent objects in this category, other items may also meet this definition. Some examples include:
Penetration of the skin with a biologically contaminated sharp device is one of the most efficient means of transmitting infection. In order to minimize the risk of a sharps injury the following guidelines must be followed:
3.11.1 Recapping NeedlesNeedles are not to be recapped at BSL-2 unless specifically exempted by the Biosafety Office. Needle recapping is discouraged at BSL-1, but if necessary, the one-handed scoop technique may be used. If research activities create the need to recap needles, your lab should submit the needle re-capping exclusion form to the Biosafety Office. In rare instances where re-capping is permissible, utilize the one-handed scoop method. First, place the cap in a flat surface. Second, using one hand, scoop the cap up with the needle. Third, using the same hand, “click” the cap in place by pressing with your thumb at the base of the needle cap. 3.12 BIOHAZARDOUS WASTE MANAGEMENTINFECTIOUS WASTE COLLECTION, DISINFECTION, AND DISPOSAL 3.12.2.1 Liquids Liquid wastes may be treated and disposed of by either of the following methods:
OR
3.12.2.2 Sharps Biohazardous sharps waste must be disposed in an FDA-approved container that is manufactured for the disposal of biohazardous sharps waste: 1) puncture resistant; 2) restricted opening disallowing retrieval of sharps; 3) a lid that can be securely closed once full; and 4) labeled with the universal biohazard symbol. Additionally:
3.12.2.3 Solids Treatment of solid, non-sharps biohazardous waste may occur in two ways:
NOTE: If other methods of decontaminating and disposing of biohazardous waste are desired, validation data specific to the requested alternative method may be submitted to the Biosafety Office for review. 3.12.2.4 Serological Pipettes Suggested practices:
3.12.2.5 Pathological Waste Pipette wastes may require creative approaches for accumulation prior to disposal. Serological pipettes and micropipette tips are good examples, as they may not fit some biohazardous waste bins or may present a sharps hazard if they comingle with heavier wastes (e.g., agar plates). Animal tissues, tissue trimmings, organs, or carcasses must be:
NOTE: Never discard pathological wastes into the trash! Biohazardous Waste Training
3.12.4.1 Autoclave Use and Safety: Validations In accordance with local and state regulations, all biohazardous waste must be biologically-inactivated before it is disposed of as trash. This can only be achieved if the waste is exposed to the right temperature for the right amount of time. Optimally, the waste should be exposed to: 121°C, at a pressure of 15 PSIG for at least 20 minutes. If you are an autoclave validation volunteer, employ the following autoclave validation practices:
Note: biological indicators (Geobacillus stearothermophilus spore) testing may be required in some circumstances. Contact the Biosafety Office for instructions. 3.12.4.2 Autoclave Use and Safety: Bagged Waste Employ the following autoclave treatment protocol for biohazardous waste:
CAUTION: Do not autoclave wastes that are contaminated with hazardous chemicals or radiological materials!! 3.13 SPILL PREVENTION AND RESPONSESpills are a part of life in the laboratory and will occur. This means that when working with infectious or recombinant agents, precautions must be taken to reduce the number of spills and that a spill response plan must be in place.
For spills involving potentially infectious materials:Cleaning up a biohazardous spill in a biosafety cabinet
Cleaning up a biohazardous spill outside of a biosafety cabinet
Cleaning up a biohazardous spill inside a centrifuge
Note: The response outlined above refers to spills that are <500 mL. For larger spills, please contact the Biosafety Office. 3.14 EMERGENCY RESPONSE AND NOTIFICATIONAfter initial first aid, report the incident to your supervisor and seek medical attention as soon as possible. The need for these steps can arise from an incident where (not an all-inclusive list):
It is important to have pathogen/strain information for the materials you are working with available to carry with you when you seek medical attention. To ensure proper agency reporting and other remedial actions, notify your supervisor and the Biosafety office in the event of:
Emergency procedures, reporting, and medical evaluation are summarized below:
In the event of a fire, follow the actions prescribed by UT fire policies. In the event of a fire in the BSC, turn the blower off and close the sash to minimize the immediate spread of the fire and follow the actions prescribed by UT fire policies. In the event of a building evacuation while you are working with materials at BSL-2, cover the materials or leave them in the BSC. Remove your gloves and lab coat on your way out of the lab. Medical emergencies can only be responded to successfully if they’re reported. In many BSL-2 environments, the work may be done by one individual in a culture room or an isolated area of the lab where a person may not be readily visible. Therefore, anyone who will be working at BSL-2 should assure that at least one other person in the lab group knows that they will be working, and the person notified should check on them frequently to assure that they are alright. If a medical emergency arises for someone in your lab who is working with materials requiring BSL-2 containment, call EMS (by way of 911) immediately. While life safety is first and foremost, some basic actions should be taken to minimize the spread of contamination.
For injuries not related to an exposure event (i.e. back strain, paper cut, etc.) follow the regular occupational injury reporting process. In the event of biological exposure incident, follow the procedures outlined in Section 5 (Occupational Health) of the biosafety manual. Remember to flush the exposed skin or mucous membranes for 15 minutes, report it to your supervisor and the Biosafety Office (974-1938) and to seek medical attention. All personnel experiencing an exposure to potentially infectious materials must also complete the Biosafety Incident Report form and submit the completed form to the Biosafety Office. The form may be found at https://biosafety.utk.edu/emergency-response/, or by contacting the Biosafety Office at 974-5547. After initial investigation and filling out the form, contact the Biosafety Office for communication and follow-up. The Biosafety Office encourages all lab personnel to report near miss events and unsafe conditions as well as exposures. Follow the exposure guidelines above for near misses and unsafe conditions or call the Biosafety Office. Which of the following is a good work practice when centrifuging biohazards quizlet?Which of the following is a good work practice when centrifuging biohazards? Decontaminate the exterior of tubes, safety buckets, and/or sealed rotors before removal from the biosafety cabinet.
Which of the following best describes the universal biohazard label?Which of the following best describes the universal biohazard label? Labels are fluorescent orange or orange-red with lettering and symbols in a contrasting color. What is the recommended NIOSH height (in inches) for the top opening of wall mounted sharps containers?
Which answer best describes PPE on the hierarchy of controls to protect workers quizlet?Which answer best describes PPE on the hierarchy of controls to protect workers? PPE is considered the last line of defense to protect researchers on the hierarchy of controls.
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