81 
It is a laboratory commonly used for undergraduate-level teaching purposes 
and for other activities involving microorganisms of no or minimal biohazard 
under ordinary conditions of handling. Work in this laboratory is generally 
conducted on open bench tops. Special containment equipment is neither re- 
quired nor generally available in this laboratory. The laboratory is not 
separated from the general traffic patterns of the building. Public access 
is permitted. 
Materials and equipment that contain or have come in contact with re- 
combinant DNA materials are disinfected or sterilized by autoclaving prior 
to disposal, and work surfaces decontaminated. Cotton plugged pipettes and 
mouth pipetting may be used where the hazard is minimal, but mechanical pi- 
petting devices are preferable and are required for more hazardous material. 
Pointed syringe needles are avoided where possible. Eating, drinking, and 
smoking are discouraged in the work area. Laboratory personnel should wash 
hands before and after experiments involving these materials. Laboratory 
doors are closed while such experiments are in progress. Appropriate cloth- 
ing such as clean laboratory coats, or similar apparel, and closed shoes are 
worn when handling potentially hazardous organisms. Laboratory coats are 
not worn outside the work area. Each laboratory has an effective insect- 
and rodent-control program. Any research group working with agents with a 
known or a potential biohazard has an emergency plan, including a clean-up 
procedure to follow if an accident contaminates personnel or environment. 
The principal investigator ensures that everyone in the laboratory is famil- 
iar with both the potential hazards of the work and the emergency plan. If 
a research group is working with a known pathogen for which an effective 
vaccine is available, all workers are immunized. Serological monitoring, 
where appropriate, is provided for. 
P2 Level (Low) . A laboratory suitable for experiments involving re- 
combinant DNA molecules requiring physical containment at the P2 level is 
similar in construction and design to the PI laboratory (Figure 2). The P2 
laboratory has access to an autoclave, within the building; it may have a 
Biological Safety Cabinet. Work which does not produce a considerable 
aerosol is conducted on the open bench. Although this laboratory is not 
separated from the general traffic patterns of the building, access to the 
laboratory is limited when experiments requiring P2-level physical contain- 
ment are being conducted. Experiments of lesser biohazard potential can 
be carried out concurrently in carefully demarcated areas of the same 
laboratory. 
The P2 laboratory is typical of laboratories found in diagnostic fac- 
ilities and college and university departments of microbiology. The labora- 
tory is commonly used for experiments involving microorganisms or ordinary 
potential biohazard, such as those which have been classified by the Center 
for Disease Control as Class 2 agents. 
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