ABSTRACT
The prologue to this book outlines the broad defining characteristics – the four cornerstones – of Resilience Engineering. One of these is monitoring. Every organisation concerned with safety has one or more metrics that are used to judge whether the levels of safety in the organisation are acceptable. Using a common definition of safety, the organisation needs to know if it is ‘free from unacceptable risk’. This metric is often the number or rate of accidents or injuries (or deaths) over some period of time or the time between events as shown by Figure 5.1. Typical industrial safety sign https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315605692/489600bf-8bc6-4472-836b-ca041c59245e/content/fig5_1_OB.tif"/> (Photo © Sheena Chi, 2009)
