Containment biosafety levels

It is an aerobic, gram-negative, motile, nonsporing, rod-shaped bacterium. It can survive for many months in surface water and up to 3 months in shaded soil. The natural reservoir is soil and water. This is a biosafety level 2 agent. Additional primary containment and personnel precautions may be indicated for activities with a high potential for aerosol or droplet production. 

The "P" has been replaced with "BSL" or Biosafety Level. There are four biosafety levels which are defined according to a combination of facility design, laboratory practices and techniques, equipment and health and safety controls. It is not practical to try to completely describe all of the features and definitions pertaining to biocontainment laboratories in a chapter dedicated to an overview of design. Therefore, we will concentrate on the elements of building design for "maximum containment" or BSL-4 facilities. 

Biosafety Level 4 (BSL-4) Important procedures for BSL-4 and BSL-3 laboratories (as well as BSL-2 and BSL-1) are contained in a valuable 250-page manual, Biosafety in... 

BSL 2 Biosafety Level 2 is suitable for work involving microorganisms of moderate potential hazard to personnel and the environment. Safety equipment Class I or II biosafety cabinets or other physical containment devices laboratory coats, gloves, face protection as needed. Microorganisms include hepatitis B virus, HIV, salmonellae, and mycoplasma. 

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 washing hands. Special containment equipment or facility design is not required nor is it generally used. 

World Health Organization (WHO) identify Biosafety Levels 1,2, 3, and 4 and in the United Kingdom the Advisory Committee on Dangerous Pathogens (ACDP) categorizes Laboratory Containment Levels 1, 2, 3, and 4 (4-6). All share the same objective to identify biosafety or laboratory containment levels that minimize the risk to the laboratory worker, to the outside community, and to the environment. At Biosafety/Laboratory Containment Level 2, exposure risks to the laboratory worker arise mainly from contact through a contaminated work environment. As the risk of airborne infection increases, Biosafety/ Laboratory Containment Level 3 provides facilities to prevent aerosol transmission. Additional safeguards to protect the outside community and the environment are found at Biosafety/Laboratory Containment Level 4, which is... 

OM-10.1 cells express passagable virus (2), although viral titers do not recover on serial passage indicating some viral defect. Therefore, increased end point HIV-1 titers after TNF-a induction can be used to evaluate drag effects in place of or in addition to supernatant RT activity. Furthermore, appropriate biosafety level containment should always be observed when working with OM-10.1 cultures or products. 

Table I summarizes the practices necessary for four biosafety levels of containment of plants. Biosafety level 1 would be similar to a standard greenhouse, with the containment precautions becoming more strict at higher levels. The IBC would recommend the appropriate containment level for each experiment and will be responsible for assuring that the principal investigator adheres to the approved practices for that project.

The Guidelines then described in detail certain laboratory practices and equipment that defined four levels of "physical containment" called PI, P2, P3, and P4. (These have been modified slightly in the current Guidelines and now are are called Biosafety Levels 1 to 4 (BLl to BL4).)... 

To prevent brucellosis, animal handlers should wear appropriate protective clothing when working with infected animals. Meat should be well-cooked milk should be pasteurized. Laboratory workers should culture the organism only with appropriate Biosafety Level 2 or 3 containment (see Chapter 19, The U.S. Biological Warfare and Biological Defense Programs, for a discussion of the biosafety levels that are used at the U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland). 

N o special containment devices or equipment such as a biological safety cabinet are usually required for manipulations of agents assigned to biosafety level 1. 

Biological materials to be removed from the class III cabinet or from the biosafety level 4 laboratory in a viable or intact state are to be transferred to a nonbreakable, sealed primary container and then enclosed in a nonbreakable, sealed secondary con-tainer, which is to be removed from the facility through a disinfectant dunk tank, fumigation chamber, or an airlock designed for this purpose. 

All procedures within the facility with agents assigned to biosafety level 4 are to be conducted in C lass 111 biological safety cabinets orin Class 11 biological safety cabinets used in conjunction with one-piece positive pressure personnel suits ventilated by a life support system. Work with vital agents that require biosafety level 4 secondary containment capabilities can be conducted in class 11 biological safety cabinets within the facility without the one-piece positive pressure personnel suit if ... 

Animal work with viral agents that require Biosafety Level4 secondary containment,and forwhich highly effective vaccines are available and used, may be conducted with partial containment cages and without the one-piece positive pressure personnel suit if the facility has been decontaminated,no concurrent experiments are being done in the facihty which require Biosafety Level 4 primary and secondary containment, and all other standard and special practices are followed. 

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