Tolerable risk is the term used for the past several years referring to a level of residual risk for a given hazard after applying risk reduction measures. ANSI B11.TR3; 2000 further defines tolerable risk as: Risk that is accepted for a given task and hazard combination [hazardous situation]. However, as more focus continues to be directed at integrating the safety mindset into all phases from womb to tomb of a machine life cycle, a more current term has come to life replacing tolerable risk.

Acceptable risk is the new term that is currently appearing in updated standards and which more clearly represents the implied intent of both evaluation and mitigation. The assumption is that risk can never truly be totally eliminated from a hazard but that every risk should be evaluated for risk reductions and mitigated to the smallest amount possible. Therefore, more current standards are defining acceptable risk as the level at which further risk reduction will not result in significant reduction in risk or that additional expenditure of resources will not result in significant advances towards increased safety.

So, where’s this discussion going? Does it really matter? Maybe a good analogy is in order. For example, is a zebra white with black stripes or is it black with white stripes? Isn’t the whole bottom line of the risk analysis process really about consciously establishing the importance of reducing the risk of occupational injuries, illnesses, and fatalities? Of course the answer is – YES ! So, let’s get off our laurels and get on with the program