Thursday, September 13, 2012

CSB add nice features to investigation reports

Lately I have read the CSB report on the three process safety events at DuPont's Belle site in the Khanawah Valley in January 2010. What a change it was from one of the first CSB reports I read - the one from the explosion and fire at Morton International, which was later acquired by Dow Chemical. The report about the toxic releases at the DuPont site was issued early in the fall of 2011 after less than 2 years investigation.
This report include two features, which I have not seen before: a logic tree covering all three releases and showing root causes for each of the events, and a timeline diagram showing the company history with details of the tree recent events. I wonder what information could be gained from a logic tree of all events investigated in a given year? Would such a logic tree give information about the type of systems, that failed? And maybe this changed from year to year based on external factors.
The Khanawha Valley became known in the process safety community when 18 chemical companies in the Valley compared worst case scenarios and made the information public not only at a town hall meeting by also by having plant manager face residents at a local mall the following Saturday. The LEPC commended at the time the companies for making the information public. Since then there has been a number of events, which got the attention of the CSB. Like explosion and fire at Bayer Crop Science which almost damaged a MIC tank. According to CSB calculations the phosgene release at DuPont in January 2010 had unhealthy off-site concentrations.
Any one CSB investigation report contain valuable information about process safety events for others to learn from. The very specific nature of the investigations however mean the general learning to be gained from the investigations is somewhat difficult. Often the failing systems, such as design, training, emergency response, incident reporting, etc.are not explicitly stated. Neither is it clearly stated what systems the recommendations are aimed at. And navigational features to easily jump from e.g.the executive summary to the recommendations of interest are to a large extend missing. Hopefully this will improve.