General. The deviation which can exist between the actual performance characteristic of a component, equipment or system, and the true or required value of such performance
Peter Koob (Compiler & Typesetter, Tasmania State Emergency Service), Emergency Management Australia (Ed & Pub), Australian Emergency Management Glossary (Australian Emergency Manuals Series Part I: The Fundamentals, Manual 3), ISBN0642476152, Tasmania, Australian 1998. http://www.em.gov.au/Documents/Manual03-AEMGlossar y.PDF, (Emr Mgt/ ND and Other Dzstr - Brit) {53}