ABSTRACT
This chapter lists some estimates that have been made of the probability of error. However, these data have several limitations. First, the figures are estimates of the probability that someone will, for example, have a moment's forgetfulness or lapse of attention and forget to close a valve or close the wrong valve, press the wrong button, make a mistake in arithmetic and so on. Second, the figures are mainly estimates by experienced managers and are not based on a large number of observations. Taylor-Adams and Kirwan have published some human error failure rates based on one company's experience but their paper does not show whether the errors were due to slips or lapses of attention, poor training or instructions or non-compliance with instructions. The American Institute for Research has published a series of papers on the reliability of simple operations such as those used in operating electronic equipment.
