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The influence of systematic failures to the functional safety of automated control systems of hazardous technological processes is considered. It is shown that stability ensuring of the process control system to systematic failures is an actual task for today. Approaches to increase the robustness to systematic failures recommended by IEC 61508 are presented. Special attention is paid to methods based on diversion. The functional diversity and technology diversity have been revealed in detail. Examples of using diversification in railway automation systems are given. The main problems of using diversification to increase resistance to systematic failures are formulated. The main advantages of using diversification are increased resistance to systematic failures and reduced risk of dangerous failures through the usage of diversified protection methods at the functional levels of the APCS. The disadvantages of using diversification are a significant increase in the costs of developing and automated process control system maintenance, the difficulty of confirming the different behavior of diversified channels in case of systematic failures, and the lack of an effective method to assessing the sufficiency of the obtained diversification for a given level of safety integrity.

The article deals with the possibility of applying a conditional diagnostic algorithm, applied to a specific problem of searching for damage in a station's tonal track circuit. The aim of the work is to substantiate the possibility of applying diagnostic algorithms, in order to reduce the time of search and repair of damages. The order of compiling the diagnostic algorithm is shown, conditional probabilities, diagnostic weights, private and general diagnostic values are calculated. On the basis of the calculations performed, a conditional algorithm for diagnosing the tonal track circuit was compiled. The advantages of the conditional diagnostic algorithm in relation to the unconditional algorithm are demonstrated. The results obtained in the article can be used for technical maintenance of automation systems of operating railways.

Within the framework of the article, a study was made of the workplace of wheelchair washers for the purpose of determining the main occupational diseases and the causes of their occurrence. The theory of constructing rational modes of work and rest for working in the off-season in the open air is considered. The equation of integral index of cooling conditions is given. The risks associated with working in the cold are listed, as well as basic protection measures for workers, such as personal protective equipment and recommendations for restroom equipment. Within the framework of the article, the technological stages of manual washing of passenger carriages and a number of harmful production factors at the workplace of wheelchair washers are considered. In the process of analyzing the working conditions of the profession in question, a number of prof. diseases such as acute intoxication, dermatitis and dermatosis. The results of the conducted tests for the evaluation of the toxicity index and operational tests of samples of the detergent «Trans-Eco» with the aim of improving the working conditions of the passenger car wipers are presented.