Near misses

The Australian pipeline industry can be proud that there has never been a death or serious injury caused by failure of an operating pipeline.  But that exemplary record can hang by a thread …

The APIA/POG pipeline incident database has received reports of two events that I thought were stomach-churning scary:

  • A D10 dozer ripping to 1200 mm depth passed over a pipeline twice and stopped just short of another pipeline in the same area; the pipeline crossed was at about 1350 mm depth (phew!)
  • A 1.2 m diameter pole auger (for a large power pole) was all set up to drill on a transmission pipeline easement; it was stopped by a patroller for a separate gas distribution business who passed by on other work and just happened to notice the auger (phew!)

If the crews operating the ripper and auger were the type of people who buy lottery tickets on lucky days they should have gone and bought dozens.  (But I think that lotteries are a tax on people who can’t do maths.)

Both of these threats had been considered in a generic way in the safety management studies for the pipelines and both had been judged to be adequately controlled by the procedural measures in place.  In a sense the controls worked because there was no damage or failure but in both cases the multiple levels of protection were reduced to one (depth of cover in the case of the ripper) and nil plus luck (in the case of the auger, against which there is essentially no effective physical protection).  Paring the multiple barriers down to one or just luck is not a comfortable position.

Some general comments prompted by these incidents:

  • The industry must never be complacent about the things that might be done to pipelines (complacency is too easy when it comes to low-probability but high-consequence events).
  • Procedural protection measures can and do fail despite the fact that there may be several of them  (pipeline awareness programs, dial-before-you-dig, warning signs, etc).
  • The “controls fail” scenario in an SMS workshop can come uncomfortably true.
This entry was posted in External interference, Incidents, Operations, Risk assessment. Bookmark the permalink.

4 Responses to Near misses

  1. Anonymous says:

    Peter, A truer comment has not been penned. It is all too easy to become complacent and rest on the assumption that the engineerring decisions of the past still hold us in good stead 20 or more years later on. Contant rigourous review of risk is the only way of ensuring controls are at their best over time.

    Neil Parry

  2. petertuft says:

    Interesting comment received which I re-post here:

    Regarding close calls. On a pipeline that I was working on recently the construction rules at all facilities (10) were that “No One” uses any tools until the site supervisor was on site and the morning tool box meeting was complete. However, a fencer thought that that was all BS, arrived at the site early with his auger and started putting in fence holes. Problem was that he couldn’t read the drawings AND removed the barrier fence around the ‘No Go’ area protecting the live transmission pipe. He managed to sink his hole directly above the CL of the live 24″ pipe. Fortunately the auger stopped about 300 mm short of the pipe. I’m an I&E Engineer so although I was not directly involved, I was witness to the initial panic and the following investigation.

    By the way, a great blog, thank you for making the time to write it.

    • petertuft says:

      I love anecdotes like this. Almost every week I sit in a workshop and people assert with complete confidence that they have procedures in place (including fencing, pre-start meetings, JSEAs, etc) that will prevent this sort of thing. And yet it still happens, so stories like this are important to illustrate that all those procedural measures can only reduce the risk to a low level, they can never eliminate it.

      As I have quoted somewhere previously in this blog, “you can’t make things foolproof because fools are so damn ingenious” (or ignorant, overconfident, stupid, or some toxic combination of the lot).

  3. Pingback: Procedural controls | Pipelines OZ

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