Knowledge and Practices Regarding Usage of Biological Safety Cabinets

Survey on proper and safe use of biological safety cabinets (BSCs) in research, bio-medical and animal laboratories in Karachi, Pakistan a cross sectional study

There is currently limited knowledge about the transmission risks of the SARS-CoV-2 virus and its associated disease COVID-19 from routine clinical specimens. The first study to be published on the initial 41 cases of COVID-19 infections admitted in Wuhan detected SARS-CoV-2 RNA in the blood of 6/41 (15%) of patients.1 However, another study conducted on 1 070 clinical specimens collected from confirmed COVID-19 patients in China showed the highest positive rates of SARS-CoV-2 from real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) testing of respiratory specimens such as bronchoalveolar lavage, sputum and nasopharyngeal swabs (32%–93%). In contrast, only 1% of blood specimens and none of the urine specimens tested positive.2 Although the rates of viraemia appear to be low, it nonetheless poses a risk of potential respiratory transmission to laboratory staff via aerosolization of blood specimens during specimen processing steps such as centrifugation and vortexing. Paediatric specimens pose a particular challenge as automated analysers cannot handle small-volume samples from paediatric-sized tubes, necessitating manual handling of specimens. The Haematology Laboratory at the Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, processes over 130 000 paediatric samples annually. Our laboratory received the first sample from a suspect COVID-19 patient on 22 January 2020 and processed samples from a confirmed COVID-19 patient on 5 February 2020. From January to March 2020, we processed approximately 2 070 samples from paediatric patients with suspected or confirmed COVID-19 infection. In this paper, we describe the specimen management policy for handling and processing COVID-19-related blood samples in our laboratory, and highlight the challenges of working with paediatric samples during this period. Our laboratory had existing biosafety guidelines for specimen management from patients with emerging respiratory pathogens (SARS-CoV and MERS-CoV). In early January 2020, the Ministry of Health in Singapore alerted healthcare practitioners of the emergence of a novel respiratory infection in Wuhan.3 Following the announcement, we performed a series of risk assessments based on identification of potential hazards and available laboratory equipment and facilities. Our guidelines were regularly reviewed when documents from the Ministry of Health, Singapore Ministry of Health, Singapore,4 World Health Organization (WHO)5 and the Centres for Disease Control and Prevention (CDC)6 relating to laboratory biosafety when handling COVID-19 specimens became available. We reviewed each test offered in our laboratory and made the decision to either require consultations with the laboratory haematologists for tests with a higher risk profile or not to offer tests which could not be performed safely based on our risk assessments Table I. We redesigned the laboratory workspace such that dedicated analysers closest to the Class II biological safety cabinet (BSC) were used for COVID-related specimens in an area separated from the rest of the laboratory. Suspect Full Blood Count Coagulation assays Prothrombin time (PT) Activated partial thromboplastin time (APTT) International normalized ratio (INR) Thrombin time (TT) Fibrinogen Anti-Xa assay Blood Gas Analysis on I-Stat Parameters assessed: Sodium Potassium Ionized Calcium Glucose Haematocrit pH pCO2 pO2 TCO2 HCO3 Base excess Prior to the COVID-19 outbreak, paediatric blood specimens were collected in Becton Dickinson (BD) Microtainer EDTA microtubes (Becton, Dickinson and Company, Franklin Lakes, NJ, USA). However, this required open-mode sampling on the Sysmex XN-1000 (Sysmex Corporation, Kobe, Japan) analyser in use at our laboratory, and would have subjected staff to the risk of aerosol exposure. We had previously performed a validation study using the BD Microtainer MAP (Microtube for Automated Process) Microtube (Becton, Dickinson and Company), which is an alternative collection tube with a membrane cap allowing automated sample piercing and analysis without cap removal. Early on in the outbreak, a decision was made to switch specimen collection tubes to the MAP Microtube, avoiding the need to manually handle specimens in open mode. Paediatric blood samples for coagulation assays are collected in 3·2% sodium citrate Greiner Bio-One MiniCollect® 9NC (Greiner Bio-One GmbH, Kremsmünster, Austria) tubes. Although the tube has a membrane cap allowing for automated closed-mode analysis, the coagulation analyser in use at our laboratory (STA Compact Max (Diagnostica Stago, Asnières-sur-Seine, France)) is not equipped with the optional cap-piercing system. Specimens for blood gas analysis are collected in heparinized syringes [Becton Dickinson (BD) A-LineTM Blood Gas Analysis Syringe (Becton, Dickinson and Company). Even before receiving specimens in the laboratory, close communication with clinical areas is essential to ensure safe transport and appropriate labelling of specimens. At our institution, a disease outbreak task force (DOTF) was set up to co-ordinate management of suspect and confirmed COVID-19 patients, with representation from the laboratory to design protocols and communicate updates around laboratory-related issues. Specimens had to be double-bagged, labelled appropriately as COVID-19-related specimens and hand-delivered to the laboratory to avoid loss or misplacement of specimens. The pneumatic tube system was not used due to the risk of specimen loss and spillage. As there were limited supplies of face shields in our institution, a decision was made by hospital management to reserve the use of face shields for clinically high-risk situations, for example procedures involving suctioning of patients with confirmed COVID-19 infections. When handling and processing COVID-19-related blood samples in the laboratory, all staff must don personal protective equipment (PPE) including laboratory coats, disposable gloves, surgical masks and safety goggles which provide a good alternative for protection of the face and mucous membranes. All staff are reminded to practice good hand hygiene after processing samples and before leaving the laboratory. This policy applies round the clock. All COVID-related specimens are initially handled in the Class II BSC. Samples are carefully removed from specimen bags and manually disinfected with Mikrozid®AF (94% Ethanol, Schülke & Mayr GmbH, Norderstedt, Germany) wipes with a minimum contact time of 2 min. Samples for full blood count are loaded directly into the dedicated Sysmex XN analyser located just beside the BSC. Blood films are manually prepared in the BSC and fixed in 100% methanol for 15 min before automated staining by a Hematek (Siemens Healthcare Diagnostic Products GmbH, Marburg, Germany) stainer. Samples sent for coagulation assays are decapped in the BSC and checked for clots with applicator sticks. The samples are centrifuged using a STI PlasmaPrep (Separation Technology Inc, Sanford, FL, USA) centrifuge located within the BSC. Plasma is then aliquoted into Eppendorf tubes which are packed in a clean biohazard bag and hand-carried to the STA Compact Max coagulation analyser for analysis. A splash guard was installed beside the analyser for safe opening of the Eppendorf tubes which are then loaded into the sample drawer of the analyser. Point-of-care testing for blood gases in paediatric patients at our institution is handled mostly at clinical areas by staff in appropriate PPEs using I-Stat devices (Abbott Point of Care Inc, Chicago, IL, USA). However, specimens for blood gas analysis which includes measurement of the haematocrit (Table I) can also be analysed in the laboratory using the CG8 + cartridge on the I-Stat device, with all analysis performed within the BSC. All consumables used during processing of COVID-related samples are immediately discarded into the original specimen bags, double-bagged and disposed into a biohazard waste bin. When testing is completed, all specimens are double-bagged with new biohazard bags and stored in a locked container for three days before disposal in the biohazard waste bin. When a suspect patient tests positive for COVID-19 from rRT-PCR of respiratory samples, the Haematology Laboratory is informed by the Molecular Microbiology Laboratory within the same laboratory service. Samples from the patient are retrieved and autoclaved the next working day before disposal. Work surfaces inside the BSC are disinfected with Mikrozid® AF wipes after each use. The Sysmex XN analyser is decontaminated daily with a proprietary 5% sodium hypochlorite solution (CellCleanTM) when performing daily maintenance and shutdown procedures. The Stago Compact Max analyser is decontaminated weekly with a higher strength of sodium hypochlorite (0·5%) using the routine maintenance protocol. Biological liquid waste from both analysers is decontaminated with 5% sodium hypochlorite for at least 30 min before disposal. The management of COVID-related specimens from paediatric patients poses unique challenges. Samples from children need to be collected in small-volume tubes, which may not always be suitable for automated analysis by analysers. Repeated blood sampling is also a challenge in young children, necessitating upfront discussion between clinicians and the laboratory haematologist as to the timing and availability of tests, so that repeated blood-taking procedures are minimized. It is now recognized that children with COVID-19 infections present with less severe symptoms compared to adults, with a case series of more than 2 000 children reporting that 13% of confirmed cases were asymptomatic.7 A six-month-old infant with confirmed COVID-19 infection identified through family screening treated at our institution remained asymptomatic despite detectable viraemia.8 Compared to adults, clinical identification of potential COVID-19-infected children may not be as obvious, adding to the risk of laboratory staff unknowingly handling a blood sample with SARS-CoV-2. This is why we have reiterated to staff in our laboratory on the need to adhere to standard precautions for all samples, including the use of PPE such as laboratory coats, surgical masks, gloves and fastidious attention to hand hygiene. In this letter, we have shared our experience and challenges with management of COVID-19-related blood specimens from paediatric patients, and hope that this can serve as a guide for other laboratories who need to handle similar specimens. All authors contributed to the drafting of the COVID-19-related biosafety guidelines in use in our laboratory and to the writing of the manuscript. All authors approved the submitted version and revisions. We acknowledge Dr Clement Ho and Mr Setoh Johnson for their help with the manuscript.

Biological safety cabinets (BSCs) are the primary means of containment used in laboratories worldwide. To ensure the proper functioning of BSCs, they need to be certified annually, at a minimum, per National Sanitation Foundation (NSF)/American National Standards Institute Standard 49. A common problem most organizations face is that in many instances, the technicians who certify the cabinets are not accredited by the NSF. Additionally, in states or regions that do not have local NSF accredited field certifiers, it takes weeks to get a service request completed, thereby delaying the research work of the laboratory. Moreover, in such instances, the cost associated with cabinet certification and repair can be very high. This led the Office of Safety at the University of North Dakota to do a thorough cost-benefit analysis of developing an in-house BSC certification program. After completing the training and testing requirements for the NSF's advanced accreditation program, the BSC certification program was initiated on campus. The identified benefits led to the initiation of a program in both local and regional capacity for repair, maintenance, and certification of BSCs, and the university's experiences were shared with other universities. By developing an in-house BSC certification program, the University of North Dakota was able to reduce wait times associated with service repairs, reduce costs, and generate revenue for the department. Furthermore, this led to improved hands-on training programs related to BSC use in laboratories working with biohazardous agents.

Biological Safety Cabinet (BSC) is a laboratory work area with air ventilation that has been engineered to protect workers working with material samples, the environment and material samples from the possible danger of contamination or causing the spread of pathogenic bacteria or viruses. The purpose of this study is to analyze the stability of the time required for the BSC to reach the condition of no particles in the BSC space. This is done by making a module using the PMS7003 sensor to detect the number of particles. This study uses the Arduino Mega system for data processing and then displays it in the form of graphs and numbers. In the condition of the number of particles of 162,965, the time required for the BSC is 29 seconds, while in the condition of the number of particles of 186,408, the time required is 38 seconds. So it is known that if the number of particles in the BSC space is more and more particles in the BSC space, the longer it takes for the BSC to reach the no-particle condition. BSC that uses a single fan blower cannot achieve a stable number of particles simultaneously.

This chapter reviews the risks associated with the blood-borne pathogens of major concern for work-places handling human clinical specimens, and the evolution and efficacy of prevention methods developed to reduce exposures and transmission of infection. It is important to review the documented cases in detail in order to emphasize rational precautions for work with human specimens. The major premise involved the careful handling of all human blood and certain body fluids as if all were contaminated with human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) or other blood-borne pathogens. Standard microbiological practices form the basis for BSL-2, with additional protection available from personal protective equipment (PPE) and biological safety cabinets (BSCs) when appropriate. The National Institute for Occupational Safety and Health (NIOSH) guidelines establish criteria, such as the need to install container openings at a height of 52 to 56 in. to provide the ergonomically correct position for 95% of all adult female workers. The NIOSH guidelines also provide evaluation tools to help select the most appropriate container for the facility. Any defective personal protective equipment (PPE) must be replaced, and reusable protective clothing must be laundered and maintained by the institution. Finally, all laboratory workers must be instructed in the proper use of PPE and its location. The ultimate indication of compliance with standard (universal) precautions is the reduction in workplace exposures and infection with blood-borne pathogens.

Class II biological safety cabinets, normally used for low to moderate risk agents, are being recognized as providing a capability in certain laboratory and industrial situations whereby materials which are potentially hazardous to human health and/or to the environment may be controlled during routine processing thus providing personnel, product and environmental protection. As interest in these safety devices increases, so does the importance of understanding: what types of cabinets are available, how they are designed to function, their proper use, and how they may be expected to perform. A Class II Type A biological safety cabinet was challenged with Bacillus subtilis var. niger spores at line voltages from 85 to 130 volts in order to determine its performance during simulated brownout and power surge conditions. The cabinet, employing a 20.3 cm (8 in.) work opening passed both personnel and product protection tests at all voltages used. The cabinet, fitted with the 25.4 cm (10 in.) work opening passe...

Class II biological safety cabinets, normally used for low to moderate risk agents, are being recognized as providing a capability in certain laboratory and industrial situations whereby materials which are potentially hazardous to human health and/or to the environment may be controlled during routine processing thus providing personnel, product and environmental protection. As interest in these safety devices increases, so does the importance of understanding: what types of cabinets are available, how they are designed to function, their proper use, and how they may be expected to perform. A Class II Type A biological safety cabinet was challenged with Bacillus subtilis var. niger spores at line voltages from 85 to 130 volts in order to determine its performance during simulated brownout and power surge conditions. The cabinet, employing a 20.3 cm (8 in.) work opening passed both personnel and product protection tests at all voltages used. The cabinet, fitted with the 25.4 cm (10 in.) work opening passed the same tests with the exception of the personnel protection test at 85 volts. It was concluded that, when the stated motor-blower performance characteristics are provided, this cabinet design will perform its safety function over a considerable range of line voltages.

The biological safety cabinet is the one piece of laboratory and pharmacy equipment that provides protection for personnel, the product, and the environment. Through the history of laboratory-acquired infections from the earliest published case to the emergence of hepatitis B and AIDS, the need for health care worker protection is described. A brief description with design, construction, function, and production capabilities is provided for class I and class III safety cabinets. The development of the high-efficiency particulate air filter provided the impetus for clean room technology, from which evolved the class II laminar flow biological safety cabinet. The clean room concept was advanced when the horizontal airflow clean bench was manufactured; it became popular in pharmacies for preparing intravenous solutions because the product was protected. However, as with infectious microorganisms and laboratory workers, individual sensitization to antibiotics and the advent of hazardous antineoplastic agents changed the thinking of pharmacists and nurses, and they began to use the class II safety cabinet to prevent adverse personnel reactions to the drugs. How the class II safety cabinet became the mainstay in laboratories and pharmacies is described, and insight is provided into the formulation of National Sanitation Foundation standard number 49 and its revisions. The working operations of a class II cabinet are described, as are the variations of the four types with regard to design, function, air velocity profiles, and the use of toxins. The main certification procedures are explained, with examples of improper or incorrect certifications. The required levels of containment for microorganisms are given. Instructions for decontaminating the class II biological safety cabinet of infectious agents are provided; unfortunately, there is no method for decontaminating the cabinet of antineoplastic agents.

There is some general confusion regarding when to use a biological safety cabinet (BSC) to minimize risk from aerosol formation in Biosafety Level 2 (BSL'2) laboratories that handle enteric pathogens. A risk assessment was conducted to determine the risk involved in performing some standard microbiological manipulations. Although enteric organisms are not known to be infectious via inhalation, it was felt ingestion of droplets deposited around the work area may cause laboratory-acquired infection. Manipulations of Salmonella spp., Shigella spp., Escherichia coli 0157, and other E. coli have resulted in laboratory-acquired infection due to improper laboratory technique. Routine procedures, for example opening screw-capped bottles and wet petri dish covers, improper use of needle and septum, streaking plates, pipetting, slide agglutination, and microscopic preparations, were found to have potential to cause aerosol formation. Proper microbiological technique in combination with primary containment devices (e.g., biological safety cabinets) has been found to reduce the risk of laboratory-acquired infections when working with enteric pathogens. Laboratory workers must ensure that they use any means available to minimize these risks.

Objectives. Health care workers are exposed to various kinds of professional risks like needle stick injuries, lower back and back problems, allergies, violence and stress. Health care workers in tuberculosis laboratory are exposed to both infection and musculoskeletal system occupational disease risks because of using Class II, Type B biological safety cabinets and laboratory vortex equipment. This study was carried out to determine incidence rates and causes of the musculoskeletal system occupational diseases among health care workers in tuberculosis laboratories of two State hospitals in Ankara. Methods. Study population was composed of 16 laboratory workers in tuberculosis laboratories of two State hospitals in Ankara. Data was collected using a questionnaire. Results. Thirteen (81.2%) laboratory workers were male and three (18.8%) were female. The mean age of the subjects was 40.1 ± 7.0 years and average duration of occupation of subjects was 208.3 ± 11.6 month. According to the data, of the 16 personnel, 10 (62.5%) had occupational disease. Incidence rates of occupational diseases were as follows; 62.5% shoulder pain, 25.0% wrist pain and 18.8% elbow pain. Duration of their occupation was significantly associated with elbow pain ( p = 0.037). There was a significant relationship between hand and wrist pain and smoking ( p = 0.042). Seventy-five per cent of laboratory workers did not think they had enough information on occupational diseases, and 68.8% of them wanted to have information about occupational diseases. Discussion. The most prevalent occupational diseases among the tuberculosis laboratory workers in our sample were shoulder, elbow and wrist pains. Duration of occupation and smoking were associated with the incidence of occupational diseases.

An outbreak of pseudobacteremia due to Streptococcus pyogenes (group A streptococci [GAS]) and methicillin-susceptible Staphylococcus aureus (MSSA) was traced to the venting procedure for aerobic bottles prior to their loading into the incubator of the BacT/Alert analyzer (Organon Teknika). Bacteria shed by a laboratory worker suffering from impetigo and cellulitis contaminated the aerobic bottles of 10 patients. All blood culture isolates, in addition to the isolates from the laboratory worker, were of the same GAS M and T types. All MSSA isolates from blood cultures and the index case's hands had the same lytic phage profile. Procedural breakdowns were identified in the laboratory. Bottles were vented outside the biological safety cabinet, gloves were not worn, and unprotected needles were used for the venting procedure. The source of the aspirated bacteria that contaminated the bottles was identified and the index case was treated promptly.

Laboratory health care workers are vulnerable to infection with the Hospital Acquired Infections (HAIs) while receiving, handling and disposing biological samples. Ideally the infrastructure of the lab should be according to the best practices like good ventilation, room pressure differential, lighting, space adequacy, hand hygiene facilities, personal protective equipments, biological safety cabinets etc. Disinfection of the environment, and specific precautions with sharps and microbial cultures should follow the protocols and policies of the Infection Prevention and Control Practices (IPAC). If Mycobacterium tuberculosis or Legionella pneumophila are expected, diagnostic tests should be performed in a bio-safety level 3 facilities (for agents which may cause serious or potentially lethal disease in healthy adults after inhalation). Laboratory access should be limited only to people working in it.Along with the advent of new technologies and advanced treatment we are now facing problems with the dreadful HAIs with Antimicrobial Resistant Organisms (AROs) which is taking a pandemic form. According to WHO, hundreds of millions of patients develop HAI every year worldwide and as many as 1.4 million occur each day in hospitals alone. The principal goals for hospital IPAC programs are to protect the patient, protect the health care worker (HCW), visitors, and other persons in the health environment, and to accomplish the previous goals in a cost-effective manner like hand hygiene, surveillance, training of the HCWs, initiating awareness programs and making Best Practices and Guidelines to be followed by everyone in the hospital.The initiation for the best practices in the Pathology Laboratories can be either Sporadic or Organizational. Sporadic initiation is when the laboratories make their own IPAC policies. It has been seen that in few centres these policies have been conceptualized but not materialized. Organizational initiation is much more effective since the best practices are the same for all hospitals and this helps in standardizing the policies. There are organizations which work in promoting IPAC through education, standards, and advocacy and consumer awareness. Examples of organizations working in this field are IPAC Canada, Centers for Disease Control and Prevention (CDC) USA, Infection Prevention Society UK, Asia Pacific Society of Infection Control (APSIC), World Health Organization (WHO). In Nepal organizational initiation to address the issues of IPAC has been recently taken by Healthy Life Foundation Nepal (HELF Nepal) which is an organization with the mission to inform, promote and implement best practices of IPAC to prevent HAIs in the patients as well as the healthcare workers in all healthcare settings in Nepal.In Nepal awareness on IPAC in Pathology Laboratories can be brought about by initiating trainings, surveillance, regular CMEs and demonstration of techniques to the Lab personnel. Administration will have to be involved in initiating the program and maintaining it with administrative resources and financial support. Before it is too late we have to address the issues of HAIs, AROs and safety in our laboratories.DOI: http://dx.doi.org/10.3126/jpn.v4i8.11603

Researchers from the National Institute for Occupational Safety and Health (NIOSH) investigated the use of a biological safety cabinet (BSC) in connection with an exposure to Legionella pneumophila at a research facility laboratory. The exposure occurred during the handling of bacteria-containing solutions associated with the analysis of water samples. Inhalation of the bacteria was thought to be the most likely exposure route. Bacteria escaping from the BSC via inadequate filtration of cabinet exhaust air or via leaks in the cabinet structure were considered to be two possible exposure mechanisms. Our investigation included consideration of the following issues related to BSCs: 1) the types of BSCs available for specific applications, 2) certification of the cabinets, 3) information available to users regarding cabinet uses and limitations, and 4) recordkeeping. This article briefly discusses the aforementioned issues and summarizes recommendations as they relate to an industrial hygiene program...

For medical professionals involved in cancer chemotherapy, occupational exposure of anticancer agents is considered a health risk. Education about the handling of anticancer drugs and proper use of protective equipment are important for reducing occupational exposure of anticancer drugs. Furthermore, monitoring of the contamination level of anticancer drugs is important for determining the propriety of anti-contamination methods. Cyclophosphamide (CPA) has been used as the standard drug of the contamination level; however, it is rarely detected because of the disparity between drug preparation frequency and consumption, and use of a closed system. Therefore, we chose 5-fluorouracil (5-FU) as the standard drug and attempted to monitor its contamination levels by sampling using drug absorption sheets (the coupon method). We measured contamination levels inside a biological safety cabinet (BSC) and at its lower floor, and at a preparation worktable, nurses' station worktable, its lower floor and floor of the hospital room in a chemotherapy room for outpatients of the Iwate Medical University Hospital for 3 time periods. 5-FU was detected in 72% of the coupons (n=108), while CPA was detected in only 7% of the coupons (n=108). Monitoring of 5-FU contamination levels by using the coupon method was considered useful for evaluating anti-contamination method and the contamination process.

The ongoing coronavirus disease (COVID-19) pandemic is a global public health emergency.Adherence to biosafety practices is mandatory to protect the user as well as theenvironment, while handling infectious agents. A biological safety cabinet (BSC) is themost important equipment used in diagnostic and research laboratories in order tosafeguard the product, the person, and the environment. The World Health Organization hasemphasized the use of validated BSCs in order to ensure quality of the results. There aredifferent classes of BSCs that are used in various work environments based on the need. Itis imperative to use appropriate levels of biosafety and types of BSCs in laboratoriesbased on the risk assessment of the pathogen used. During the development of COVID-19laboratories and training of laboratory staff, we came across several queries about thefunctions and selection of BSCs and realized that the knowledge about the detailedinformation on selections and applications of BSCs is scanty. There are several guidelinesregarding the biosafety aspects for diagnostic and research laboratories handlinginfectious pathogens from national and international agencies. However, there is nodetailed information on the use of appropriate types of BSCs and their functions in thecontext of Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2). In view of this,the present paper describes in detail the selection and applications of BSCs, which couldbe useful for laboratories handling or planning to handle SARS-CoV-2 and suspectedsamples.