APPENDIX E 
and isolated facilities designed for maximum containment. Each of the 
levels, P2 through PA, assumes that the techniques demanded by PI, the 
standard microbiological practices, will be followed. Furthermore, for 
each level, relevant training of personnel is mandatory. The training is 
to include the nature of the potential hazards, the technical manipulations, 
and instruction in the biology of the relevant organisms and systems. 
Specific emergency plans, to be used in case of accident, are required and 
serological monitoring, where appropriate, is to be provided. 
The third approach to the problem of containing potentially hazardous 
organisms within the laboratory is the use of biological barriers. Biological 
containment is defined as the use of host cells and vectors with limited 
ability to survive outside of very special and fastidious laboratory conditions 
that are unlikely to be encountered by escaped organisms in natural environments. 
Biological containment is an integral part of the experimental design, since 
the host and vector wil I need to be chosen, in any given experiment, with a 
view both to the purpose of the experiment and to containment. The guidelines 
stress that physical and biologic containment procedures are complementary to 
one another each one serving to control any possible failure in the other. The 
use of both in a given experiment affords much higher levels of containment than 
either one alone. Therefore, the guidelines always recommend both a particular 
level of physical containment, and a level of biological containment for any 
given experiment. The guidelines explicitly recognize that techniques which 
enhance physical containment capabilities are likely to be evolved as research 
proceeds and may reduce the needs for the standard physical containment pro- 
cedures. Such innovations are to be considered as part of the on-going review 
Appendix E — 6 
