Source of nucleic acid 
Specification Vector/ Host System 
of nucleic 
acid sequence 
Category 
Bacteria specifying 
toxins virulent to man 
Random Phage or plasmid/bacteria, 
disabled 
IV 
Plant pathogenic 
bacteria 
Random Phage or plasmid/bacteria, 
not disabled 
II 
Plant viruses 
Random Phage or plasmid/bacteria, 
not disabled 
II 
Bacteria or fungi 
non-pathogenic to man. 
animals or plants 
Random Phage or plasmid/bacteria, 
not disabled 
I 
3. CODE OF PRACTICE 
3.1 We were asked to draft a central code of practice for laboratories under- 
taking experiments involving the techniques of genetic manipulation. We 
have done this on the basis of the four levels of physical containment (I- IV) 
summarised in paragraph 2.8 above: the code of practice is set out in full in 
Appendix II, together with a table illustrating the major differences between 
the four containment levels. The following headings are used in the code, as 
far as these are applicable to the particular level of containment being described: 
Laboratory (premises and facilities) 
Biological Safety Officer 
Staff — selection 
training 
supervision 
protective clothing 
health 
discipline 
Packaging and transport of samples 
Security 
Special requirements of experiments involving laboratory animals or plants. 
3.2 In drawing up the code of practice, we have taken account of the 
code set out in the Report of the Working Party on the Laboratory Use of 
Dangerous Pathoeens and in view of the similar requirements of our category 
IV containment level and the category A level for dangerous pathogens, we 
have tried as far as possible to follow the provisions and wording of that 
Working Party’s code of practice. We also noted that a code of practice 
covering three containment levels is being prepared by Sir James Howie's 
Working Party on the Prevention of Infection in Clinical Laboratories. 
3.3 As indicated in the introduction to the code of practice, we have not 
attempted to deal with all the technical queries that may arise on various aspects 
of the recommended containment levels: we have sought rather to provide 
guidelines for the GMAG to build on in drawing up the detailed specifications 
that may be necessary for assessment of individual laboratories. 
IV- 12 
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