Multi-scenario environmental analysis methodologies are being increasingly used by researchers, mainly because the use of a single method may not be feasible for a number of reasons. In the past, when inspections were carried for insurance purposes, the inspectors or risk survey engineers would assess the facilities looking for perceived problems that existed in the environment. Then, later, employing their knowledge to evaluate the results of these observations and, fnally, studying market statistics to identify whether there were similarities between what was observed and similar historical problems. Thus, for a long time, and without specifc titles, experts at that time already employed several evaluation methodologies. This article endeavours to present relationships between two methods of technical analysis, namely: Survey and SIL – Safety Integrity Level.