RISK MANAGEMENT STRATEGIES FOR CHLORINE INSTALLATIONS

Installations which make, handle and store liquid chlorine represent o ne of the largest groups of hazardous plants which pose high levels of risk to off-site populations. For such installations, risk analysis i s one of the most important tools now being used to improve safety, by aiding decisions on the acceptability or tolerability of the risks an d thereby ascertaining the need for and nature of risk reduction measu res. This paper describes a study undertaken following a regulatory au thority requirement to enclose a particular chlorine plant in a 'conta inment' system. We seek to demonstrate how 'peopleware' issues such as human factors, training, emergency planning procedures and so on can be properly represented in a conventional quantified risk analysis, an d show how a containment system, as shown by the accurate modelling of release conditions, may not actually reduce risk to off-site populati ons. By giving proper credit to detection and response arrangements, p rocedures, training and emergency planning, aspects which most safety professionals consider to be very valuable components of a risk manage ment strategy, we were able to design a package of measures that would produce a net risk reduction significantly better than that produced by a containment approach.