Mary Kay O’Connor PSC 2008 Symposium

ACCIDENT REPORTS MAY NOT TELL US EVERYTHING

WE NEED TO KNOW

Trevor Kletz

[US] “doctors take an average of 17 years for new knowledge to be incorporated into practice…

If they didn’t learn something in school there is a good chance they never would.”

ARE ENGINEERS

ANY BETTER?

Don’t answer now.

It is easy to comment on what we read or hear but we should try to read between the lines (or listen between the sentences) to spot what might have been said but has not.

Simple examples: 1. Report: A man injured a finger while using a machine fixed to a bench. A site visit showed that the machine had been fixed parallel to the edge instead of at right angles.

2. A man fell through a clearly labelled fragile roof.

Could anyone else have prevented this or made it less likely?

A site visit showed the

ladder leading to the roof.

WHAT MESSAGE DOES THIS GIVE?

BHOPAL 1984

Most reports did not say that that the storage of MIC was convenient but not essential. It was an intermediate, not a raw material or product.

PIPER ALPHA 1988

FLIXBOROUGH 1974

Most reports did not say that the large amount of H/C in the plant was due to the low conversion and 96% recycle.

NITRATION IS THE MOST DANGEROUS UNIT PROCESS. Much product is further processed to amines. CHEMISTS SAY THERE IS NO OTHER ROUTE. Has anyone looked for one?

COLOR CODING is a cheap and simple way of making wrong connections less likely.

The most common omission is that the same accident has happened before, perhaps in the same plant. A recent major example is:

Buncefield

UNDERLYING CAUSE: Belief that cold petrol could not explode in the open air, though it had in Newark, NJ in 1983 and was reported in CEP, LPB and TCE. There were similar explosions in France in 1991 and Italy in 1995.

Two chemical engineers (both here today) interviewed by BBC mentioned Newark but UK regulators knew nothing about it.

It was no one’s job to pass this information onto the Buncefield team who, responsible only for storage, could not be expected to know it already.

Why do we miss so many recommendations, which seem almost obvious in retrospect? We can’t improve until we can answer this question.

1. Committees are consensual and their reports lack originality.

2. The senior managers who chair committees or approve reports have often lost touch with the technology. They may think, for eg, that ISD is just a fashion.

3. Committees take a narrow view of their objectives.

4. We may wish to hide the fact that we have allowed a well-known accident to happen again.

5. “Young scientists view it as their solemn duty to knock the revered old-timers off their perches. Young coastal engineers have more of a tendency to revere their elders. To criticize is almost an ungentlemanly thing to do.”

Can we replace “coastal” by “chemical”?

I HOPE NOT.

ANY QUESTIONS?

Time to knock me off my perch.

• For a copy of this PowerPoint file &/or the text file please email T.Kletz@Lboro.ac.uk.

• WARNING: ppt files may omit important qualifications and are not a substitute for the text file.