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Chlorine is a liquefied gas, and is stored in large quantities for use in the chemical industry or in water treatment (e.g. the chlorination of swimming‐pool water). Chlorine is highly toxic and if released accidentally has the potential to kill or injure people in the vicinity of the storage tank. A geographic information system (GIS) is used to determine the impact of the release of chlorine from a tank in the area surrounding a swimming‐pool at the University Putra Malaysia (UPM). Spatial impact is determined using GIS software (GeoMedia Professional 5.1). Spatial analysis and buffering command are performed to locate affected residential areas near the UPM swimming‐pool. The findings mean that the affected residential area and its population can be evacuated more quickly and smoothly.

The subject of this paper is high temperature corrosion in chlorine and hydrogen chloride gaseous environments. The discussion will be limited to metals and alloys such as iron and carbon steel, iron‐chromium alloys and stainless steels, nickel and nickel alloys which are of interest in the petroleum industry.

Aims to study the behaviour of four polycrystalline carbon steels in basic pitting solutions.

Electrochemical investigations were carried out on four steels: Fe.06C, Fe.18C, Fe.22C and Fe.43C. The analysis was made using an X‐ray fluorescence apparatus. The performance indicator was the pitting potential, which was obtained through potentiodynamic sweeping. Emphasis was placed on the influence of the pH, chlorine concentration, phase proportions in the steel and the initial electrode surface state.

The results showed that in a solution with a low chlorine concentration, the performance of the steels according to pitting corrosion resistance decreased with the increase in carbon content. By raising the chlorine concentration, the order of performance was inverted gradually, while at a high chlorine concentration, the behaviour of the steels tended to be similar. The interpretation of the results is based on the consideration of cathodic reactions on the level of the cementite phase and the difference in the local chemical properties of the solution. In neutral solutions, pitting potentials were shifted cathodically, but the main observations developed for basic solutions remained valid.

Provides further research on pitting corrosion.

Until recently, chlorine used to be an important chemical in bleaching process in paper industry, but as a result of environmental concerns, it is being replaced by chlorine dioxide. However, chlorine dioxide is more corrosive in certain conditions. Plant personnel, therefore need to better understand the reactions taking place in the changed media and search for more resistant materials. It is with this in mind that the present work was undertaken. The paper reports the electrochemical polarisation measurements performed on stainless steels 316L, 317L, 2205 and 254SMO in chlorine dioxide solutions to observe localised corrosion. The results have been analysed with reference to Pourbaix diagrams, taking into account the various chemical species present in the bleach solutions. Conclusions drawn from electrochemical tests have been compared with those from long‐term laboratory and plant tests. Materials options are proposed on the optimal choice of materials for bleach plants, in a context of probable corrosion performance, capital cost and mechanical strength.

A large number of resins and polymers are used as film formers. These have been undergoing modifications to meet the growing demand. One of the modifications involves chlorination and products like chlorinated rubber, chlorinated biphenyls, chlorinated paraffins, chlorinated poly(vinyl chloride), chlorinated polyethylene, chlorinated polypropylene and chlorinated polyether are the result. Besides these well‐established chlorinated products, chlorinated drying and semi‐drying alkyds, chlorinated epoxy esters and chlorinated acrylic polymers have also been studied.

An earlier paper gave the background to the rôle of chlorofluorocarbons (CFCs) in the observed depletion of the Earth's stratospheric ozone, plus details of the Montreal Protocol that restricts the production and consumption of CFCs. In this paper, recent data on both the ozone depletion and the global greenhouse warming that result from CFC emissions are given. The progress by the chemical companies to identify replacements for CFCs is also discussed.

Reviews some of the chemistry and environmental hazards associated with chlorine and bromine compounds when used as water disinfectants in many industrial processes. Lays emphasis on the oxidation of bromide by chlorine to bromate, a suspected genotoxin. A risk assessment of the predicted presence is detailed. In view of the formation of haloforms and other noxious substances derived from chlorine, some of the advantages of the use of chlorine dioxide are detailed. Proposes recommendations for water regulators to consider the inclusion of bromine‐containing substances, and in particular bromate, in forthcoming legislation.

The evolution of a semi‐open cooling circuit of a nuclear reactor was monitored over a two year period. The work aims to provide orientation elements for preventive procedures against localised corrosion.

The water of the circuit was analysed in stagnation and in circulation, at various sampling points. The rust was analysed by neutron diffraction and the surface quality of the steel was checked by microscopic observations.

The obtained results did not confirm the presence of rust in iron compounds supported by chlorine, such as the Akaganeite, β‐FeOOH. In addition, chemical analysis of water showed that, after two years, the increase of chlorine concentration and water conductivity remained weak. Moreover, the pH was maintained within values favourable rather to the passivation of the steel.

It was deduced through this work that the dosing of the circuit with chlorine was not sufficient that it should require an annual replacement of the water.

The originality of this work resides in the evaluation of a semi‐open coolant circuit in service for ten years and located in an area subjected to seasonal sand winds.

MURGATROYD's Salt & Chemical Co. Ltd. have operated a battery of Hooker cells at Elworth, Cheshire, for the electrolysis of brine to produce chlorine, caustic soda and hydrogen since 1950. In the present review, a summary is given of the steps taken to find the most suitable materials for the chlorine take‐off pipes from the cells to the chlorine collecting main.