In the field of air pollution monitoring and dust emissions measurement, deregulation threatens a trend towards oversimplification. Over-simplification encourages the use of instruments and techniques which may seem politically attractive, but which may unfortunately not provide the more useful information which enables plant operators to obtain critical ＇trending and recording＇ data to assist in process control, and hence offer the real benefits of monitoring. Here William Averdieck of PCME Ltd looks at the choices available to companies striving to meet Environmental Protection Act regulations, while keeping down the running costs of their bag filter arrestment plants.