Health and safety research 1975 : an account of the executive's research testing and laboratory services incorporating the annual report of the Safety in Mines Research Establishment.

  • Health and Safety Executive
Date:
1976
Catalogue details

Licence: Open Government Licence

Credit: Health and safety research 1975 : an account of the executive's research testing and laboratory services incorporating the annual report of the Safety in Mines Research Establishment. Source: Wellcome Collection.

    58/66 (page 48)
    to random failure. The devices are assumed to be prone to two modes of failure, one which is readily detectable in service, and one which is undetectable in service. The expressions take into account the effects of preventive maintenance procedures in which devices are inspected at regularly spaced times to discover and renew devices which have failed ‘detectably’, and also devices are replaced after a specified age in service to mitigate the effects of ‘undetectable’ failures. These expressions are evaluated for devices having constant failure rate (i.e. exponential failure distributions) for both modes of failure; and also for a constant ‘detectable’-failure rate and an increasing ‘undetectable’-failure rate (i.e. represented by a second order gamma function failure distribution). An interview machine for collecting accident data TD Proctor Symposium Collection, Analysis and Interpretation of Accident Data 1975 Paper C6 Sheffield: Safety in Mines Research Establishment A description is given of a machine which has been designed to ‘interview’ men about their accidents. This machine, developed from a commercially made ‘teaching machine’ displays questions on a screen; the accident victim responds by pressing numbered buttons. The information is obtained in a form which is easily decoded for analysis by computer. Preliminary trials with the prototype machine at a colliery are reported and discussed. A novel method of collecting information TD Proctor and NJ Cutts Occupational Health 1976 28 302-07 A questionnaire machine developed at the Safety in Mines Research Establishment is being used to collect information on accidents. The machine is designed to reduce the amount of form-filling, to eliminate the need for interviews and to facilitate the storage and analysis of the data it gathers. The technique has been used in mining but it is expected to find application in other fields. Extinction phenomena in liquids A F Roberts Fifteenth International Symposium on Combustion 1974 305-13 Pittsburgh: The Combustion Institute A burning liquid is extinguished when its surface temperature is reduced to the fire point of the liquid. The fire point depends on properties of the liquid and of the atmosphere in which it is burning and a theoretical relationship is given which describes this dependence. This relationship is used to calculate the variation of fire point and critical heat loss at extinction of n-butanol with the oxygen concentration of the ambient atmosphere. The proximity of heat sinks to the surface of a burning liquid may cause extinction and this effect was studied experimentally; the data suggested that liquid layers up to 0-5 mm deep were stationary and heat losses from the surface to the heat sink took place by conduction. Effects of convection were apparent for greater liquid depths. For multi-component liquids, mass transfer in the liquid phase also plays a part in determining extinction behaviour. The effects of the degree of internal recirculation on the relationship between the mean composition of a liquid mixture, the surface concen- tration and the composition of the evolved vapour are discussed. Data illustrating the importance of these effects are given for the ethanol/water system; the minimum concentration of ethanol which would sustain burning in air varied from 7 to 45%, depending on the degree of recirculation within the liquid. A burner was developed in which the effects of heat and mass transfer in the liquid phase and the oxygen concentration of the surrounding atmosphere on the extinction of a burning liquid could be studied. Some early experiments with this burner are described. Dust sampling with the continuously recording instrument SIMSLIN RJ Seaney and D Barker Colliery Guardian 1975 223 532-33 The Safety in Mines Research Establishment has recently developed a continuously recording instrument, SIMSLIN, for monitoring the airborne concentration of respirable-size dust. Details of the instrument and its performance in various dust clouds generated in the laboratory have been published elsewhere. SIMSLIN has full Intrinsic Safety and Flameproof approval for use in coal mines and is now being used in a series of underground proving trials. This article gives some examples of the results obtained so far. Experimental use of a paper questionnaire CR Senneck Symposium Collection, Analysis and Interpretation of Accident Data 1975 Paper C5 Sheffield: Safety in Mines Research Establishment The experimental use of a paper questionnaire designed to elicit detailed information about the circumstances of loss-of-balance accidents in coal mines is described. The experiment ran for nearly two years throughout the Doncaster Area of the National Coal Board and involved injured men being interviewed by their colliery Safety Officers. The coverage and accuracy of the responses are considered and an example is given to show how the information obtained can lead to remedial measures. It is concluded that an interview/ questionnaire system is a practicable method for collecting detailed information about particular types of accident.