Biosafety level 63942 221837879 2008-06-26T09:25:36Z Welshdragon0586 7376721 /* External links */ A '''Biosafety Level''' is the level of the '''biocontainment''' precautions required to isolate dangerous [[biological agent]]s in an enclosed facility. The levels of containment range from the lowest biosafety level 1 to the highest at level 4. In the United States, the [[Centers for Disease Control and Prevention]] (CDC) have specified these levels.<ref name=BMBL>{{cite book | author = Richmond JY, McKinney RW (editors) | title = Biosafety in Microbiological and Biomedical Laboratories | edition = 4th ed. | publisher = | year = 1999 | url= http://www.cdc.gov/od/ohs/biosfty/bmbl4/bmbl4toc.htm | id = ISBN 0-7881-8513-6 }}</ref> In the [[European Union]], the same biosafety levels are defined in a [[European Union directive|directive]].<ref>Council Directive 90/679/EEC of 26 November 1990 on the protection of workers from risks related to exposure to biological agents at work, OJ No. L 374, p. 1).</ref> However, in USAMRIID(United States Army Research Institute of Infectious Diseases) classify agents the range from the lowest biosafety level 0 to the highest level 4 without level 1. ==Rationale== Biocontainment can be classified by the relative danger to the surrounding environment as biological safety levels (BSL). [[As of 2006]], there are four safety levels. These are called ''BSL1'' through ''BSL4'', with one anomalous level ''BSL3-ag'' for agricultural hazards between BSL3 and BSL4. Higher numbers indicate a greater risk to the external environment. ''See [[biological hazard]]''. At the lowest level of biocontainment, the containment zone may only be a [[fume hood]] that utilizes [[HEPA]] filters. At the highest level the containment involves isolation of the organism by means of building systems, sealed rooms, sealed containers, personal isolation equipment similar to "space suits" and elaborate procedures for entering the room, and decontamination procedures for leaving the room. In most cases this also includes high levels of security for access to the facility, ensuring that only authorized personnel may be admitted to any area that may have some effect on the quality of the containment zone. This is considered a hot zone. == Levels == ===Biosafety Level 1=== This level is suitable for work involving well-characterized agents not known to consistently cause disease in healthy adult humans, and of minimal potential hazard to laboratory personnel and the environment (CDC,1997).<ref name=richmond>[http://www.cdc.gov/OD/ohs/symp5/jyrtext.htm The 1, 2, 3's of Biosafety Levels<!-- Bot generated title -->]</ref> It includes several kinds of bacteria and viruses including [[Canidae|Canine]] [[hepatitis]], ''[[Escherichia coli]]'', [[Varicella]] ([[Chicken Pox]]), as well as some cell cultures and non-infectious bacteria. At this level precautions against the biohazardous materials in question are minimal, most likely involving gloves and some sort of facial protection. The laboratory is not necessarily separated from the general traffic patterns in the building. Work is generally conducted on open bench tops using standard microbiological practices. Usually, contaminated materials are left in open (but separately indicated) trash receptacles. Decontamination procedures for this level are similar in most respects to modern precautions against everyday viruses (i.e.: washing one's hands with anti-bacterial soap, washing all exposed surfaces of the lab with disinfectants, etc). In a lab environment, all materials used for cell and/or bacteria cultures are decontaminated via [[autoclave]]. Laboratory personnel have specific training in the procedures conducted in the laboratory and are supervised by a scientist with general training in [[microbiology]] or a related science. ===Biosafety Level 2=== This level is similar to Biosafety Level 1 and is suitable for work involving agents of moderate potential hazard to personnel and the environment.<ref name=richmond/> Includes various bacteria and viruses that cause only mild disease to humans, or are difficult to contract via [[aerosol]] in a lab setting, such as hepatitis [[Hepatitis A|A]], [[Hepatitis B|B]], and [[Hepatitis C|C]], [[Influenza A]], [[Lyme disease]], [[Dengue fever]], [[Salmonella]], [[Mumps]], ''[[Bacillus subtilis]]'', [[Measles]], [[HIV]],<ref>"Routine diagnostic work with clinical specimens can be done safely at Biosafety Level 2, using Biosafety Level 2 practices and procedures. Research work (including co-cultivation, virus replication studies, or manipulations involving concentrated virus) can be done in a BSL-2 facility, using BSL-3 practices and procedures. Virus production activities, including virus concentrations, require a BSL-3 facility and use of BSL-3 practices and procedures", see [http://www.cdc.gov/od/ohs/biosfty/bmbl4/bmbl4s6.htm Recommended Biosafety Levels for Infectious Agents].</ref> [[Scrapie]]. BSL-2 differs from BSL-1 in that: # laboratory personnel have specific training in handling pathogenic agents and are directed by competent scientists; # access to the laboratory is limited when work is being conducted; # extreme precautions are taken with contaminated sharp items; and # certain procedures in which infectious aerosols or splashes may be created are conducted in [[Class II cabinet|biological safety cabinet]]s or other physical containment equipment. ===Biosafety Level 3=== This level is applicable to clinical, diagnostic, teaching, research, or production facilities in which work is done with indigenous or exotic agents which may cause serious or potentially lethal disease as a result of exposure by the inhalation route.<ref name=richmond/> Includes various bacteria and viruses that can cause severe to fatal disease in humans, but for which vaccines or other treatment exist, such as [[Anthrax disease|Anthrax]], [[West Nile virus]], [[Venezuelan equine encephalitis]], [[Eastern equine encephalitis]], [[Severe Acute Respiratory Syndrome|SARS]], [[Tuberculosis]], [[Typhus]], [[Rift Valley fever]], [[Rocky Mountain spotted fever]], [[Yellow fever]]. Laboratory personnel have specific training in handling pathogenic and potentially lethal agents, and are supervised by competent scientists who are experienced in working with these agents. This is considered a neutral or warm zone. All procedures involving the manipulation of infectious materials are conducted within biological safety cabinets or other physical containment devices, or by personnel wearing appropriate personal protective clothing and equipment. The laboratory has special engineering and design features. It is recognized, however, that some existing facilities may not have all the facility features recommended for Biosafety Level 3 (i.e., double-door access zone and sealed penetrations). In this circumstance, an acceptable level of safety for the conduct of routine procedures, (e.g., diagnostic procedures involving the propagation of an agent for identification, typing, susceptibility testing, etc.), may be achieved in a Biosafety Level 2 facility, providing # the exhaust air from the laboratory room is discharged to the outdoors, # the ventilation to the laboratory is balanced to provide directional airflow into the room, # access to the laboratory is restricted when work is in progress, and # the recommended Standard Microbiological Practices, Special Practices, and Safety Equipment for Biosafety Level 3 are rigorously followed. The decision to implement this modification of Biosafety Level 3 recommendations are made only by the laboratory director. ===Biosafety Level 4=== This level is required for work with dangerous and exotic agents that pose a high individual risk of aerosol-transmitted laboratory infections, agents which cause severe to fatal disease in humans for which vaccines or other treatments are ''not'' available, such as [[Bolivian hemorrhagic fever|Bolivian]] and [[Argentine hemorrhagic fever]]s, [[Smallpox]] (there is a vaccine), [[Marburg virus]], [[Ebola virus]], [[hemorrhagic fever with renal syndrome|Hantaviruses]], [[Lassa fever]], [[Crimean-Congo hemorrhagic fever]], and other various [[viral hemorrhagic fever|hemorrhagic]] diseases.When dealing with biological hazards at this level the use of a [[Hazmat suit]] and a self-contained oxygen supply is mandatory. The entrance and exit of a Level Four biolab will contain multiple showers, a vacuum room, an [[ultraviolet]] light room, and other safety precautions designed to destroy all traces of the biohazard. Multiple airlocks are employed and are electronically secured to prevent both doors opening at the same time. All air and water service going to and coming from a [[Biosafety level#The Levels|Biosafety Level 4]] lab will undergo similar decontamination procedures to eliminate the possibility of an accidental release. Agents with a close or identical antigenic relationship to Biosafety Level 4 agents are handled at this level until sufficient data is obtained either to confirm continued work at this level, or to work with them at a lower level. Members of the laboratory staff have specific and thorough training in handling extremely hazardous infectious agents and they understand the primary and secondary containment functions of the standard and special practices, the containment equipment, and the laboratory design characteristics. They are supervised by qualified scientists who are trained and experienced in working with these agents. Access to the laboratory is strictly controlled by the laboratory director. The facility is either in a separate building or in a controlled area within a building, which is completely isolated from all other areas of the building. A specific facility operations manual is prepared or adopted. Building protocols for preventing contamination often uses negatively pressurized facilities, which, if compromised, would severely inhibit an outbreak of aerosol pathogens. Within work areas of the facility, all activities are confined to Class III biological safety cabinets, or Class II biological safety cabinets used with one-piece positive pressure personnel suits ventilated by a life support system. The Biosafety Level 4 laboratory has special engineering and design features to prevent microorganisms from being disseminated into the environment. The laboratory is kept at negative air pressure, so that air flows into the room if the barrier is penetrated or breached. Furthermore, an [[airlock]] is used during personnel entry and exit. == See also == * [[Biological hazard]] * [[Safety engineering]] * [[Security engineering]] ==References== {{reflist}} == External links == * [http://www.TradelineInc.com/BIO2008 The 2008 International Conference on Biocontainment Facilities] {{Bioterrorism}} [[Category:Safety]] [[Category:Biology]] [[Category:Biological hazards]] [[de:Biologische Schutzstufe]] [[es:Niveles de bioseguridad]] [[fr:Laboratoire P4]] [[id:Level keselamatan biologi]] [[nl:Biosafety Level]] [[ja:バイオセーフティーレベル]] [[simple:Biological hazard#Biosafety_levels]]