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BS PD 6519 contains a comprehensive bibliography of references. It is probably the best and most up-to-date summary of the subject of electric shock that can be found. 2 also discuss this subject with an emphasis on the experiences of HM Electrical Inspectors of Factories who investigated many serious and fatal electric shock accidents in Great Britain. 1 and attempts have been made to apply these to the design of electrical equipment. Once a person is 'held', not only will the experience be very painful but it may eventually prove fatal, particularly because a high resistance fault may easily develop into a more serious failure.

This is the conventional (mathematical) way of expressing the matter. This could, for example, be applied to the distribution of fatal electric shocks at varying currents, but it is not always the most useful way of illustrating the problem. 3(b) represents the same problem but with the curve scaled to give the relative probability that a particular current X would be fatal. In this case the area of the curve will not be unity. 8 The Poisson distribution or law of small numbers 27 In practice, although both curves indicate the most dangerous current, very often neither is directly useful because the shock voltage is the only thing we know after an accident and the resistance of the body at the time of the accident cannot be known.

Are time dependent). 15), and is fundamental in the interpretation of several British Standards. 15 below shows how the variation of routine test results of materials or components during manufacture can be maintained within reasonable limits by quality control. 7 which would be called a 99% confidence range or limits. The upper and lower limits may not be symmetrically spaced about the norm. g. 9. The operation of such devices is not completely predictable and occasional maloperation must be accepted.