ABSTRACT
This chapter illustrates the use of the total systems approach to develop and implement complete analytical schemes. The first example shows how the Laboratory of the Government Chemist (LGC) was able to meet a requirement for twice-yearly ‘league tables’ of the tar and nicotine yields of cigarettes sold in the UK. The instrumentation described was installed in a period between 1972-1978, however, the problem involves many aspects of automation and serves to illustrate a number of useful points, especially relating to specification details. The development was stepwise, and it passed through an initial phase where classical manual methods were used in conjunction with a computer bureau, which, with programs developed at the LGC, processed the analytical data. The achievement of total systems automation involves automation of the analytical methods and the generation of an on-line data processing system utilizing an in-house Rank Xerox RX-530 computer. Administrative and technical constraints influenced the development philosophy, which is described in detail. It will be clear to the reader that the solutions outlined in this chapter may not necessarily use computing techniques available now. Despite this, the lessons of automation are useful to the system designer and clearly show the advantages of taking a total systems approach. In addition, the size and scope of the survey changed markedly throughout the period of development. Close co-operation between the analysts involved in the day-to-day work, the managers and the Laboratory Automation Group, meant that it was possible to cope with these changing demands. The constraints came from government and industry; a desire to have the manufacturers’ agreements to the publication of the data required considerable additional consultancy at all stages. Whenever a new approach was to be used, it had to be fully validated before introduction into the scheme.
