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I think safety is a good term for directionally setting goals or performance – and for communicating with the public – but for precision one really needs to talk about risk. A key question when talking about safety (e.g., for different disciplines, activities, or outcomes) is how safe is safe enough. The Meriam-Webster Dictionary defines safety as the condition of being safe from undergoing or causing hurt, injury, or loss; and safe, as free from harm or risk. I find this confusing as it conflates risk and safety. This ambiguity is overcome when safety is put into context using a risk analysis. Here, I really like how Kaplan and Garrick, in their 1981 paper On The Quantitative Definition of Risk (See https://www.nrc.gov/docs/ML1216/ML12167A133.pdf) . Kaplan and Garrick break risk analysis down into answering these three questions: 1. What can go wrong? 2. How likely is it to go wrong? 3. If it does go wrong, what are the consequences? Kaplan and Garrick call this a triplet<S, P, X> where S is a scenario identification or description; P, is the probability of that scenario; and X, is the consequence or evaluation measure of that scenario, i.e., the measure of damage.
In terms of examples…The built environment will always have inherent uncertainty (e.g., loading and material properties) but we can manage the risk to a safe level by application of safety factors in ASD or load and resistance factors LRFD design. The underlying probability of failure is probably in the 10-4 to 10-5 range. The realm of codes and standards is to package this in a way that achieves consistent and repeatable safe outcomes and allows us to communicate safety to the public in a simplified manner. Alternatively, safety in the context of the workers that construct the bult environment is another matter. Here we strive to eliminate risk through procedures and protocols. These would include not walking under suspended loads, using fall protection when working at heights, staying out of the line of fire, etc.
I think most everything we do as civil engineers involves managing risk to acceptably safe levels through implicit or explicit action. Safety is a shorthand for communication.