Maintain your mitigation systems - they are your last lines of defense

A news report mentions that a hydrofluoric acid leak in a plant has been effectively contained by the plants mitigation systems, which worked as they were intended to do. Many of operating personnel (myself once included!) do not give enough importance to mitigation systems thinking that they will never be needed. Mitigation systems (dyke walls water sprays, interceptor dykes etc) are not required normally but are very useful in low frequency high potential incidents. In the said incident the article mentions that the company says that they haven't had a leak like this in "years and years".
Read the article in this link