The client has approved this posting as they want to make sure others can learn from their incident. PLEASE discuss this incident with your teams if your LOTO practice(s) resemble theirs – what they did was VERY COMMON and I teach this method in all my LOTO courses at process plants. I have revised my training and written program as a result of this incident, and I hope many of you will do the same.
We were involved in an investigation regarding the release of HAZMAT during servicing and maintenance, and although the investigation was clear cut, the act that caused the release and injuries involved a VERY COMMON LOTO practice in the process industries. Have you ever seen a piece of equipment, say a very large compressor, that has dozens of isolation points locked out with the use of cable, isolation devices, and a SINGLE LOTO Lock?
In my career, this was very common, especially in Motor Control Centers during a unit shutdown/turnaround (SD/TA). We would throw all of the disconnects to the OFF/OPEN position and then run a cable (a substantial cable that required bolt cutters to remove) through all the disconnect handles. We would then join the two ends of the cable and place a SINGLE LOTO lock – this would/could lock out 100 electrical disconnects at the same time with just a single lock.
NOTE: Please read my other LOTO articles on the pros and cons of this type of LOTO, as when they all get LOTO’ed under the same lock, they will be started up at the same time, or you will have to jump through a million hoops, if you want to remove a disconnect from this system so it can be returned to service sooner!
Our incident involved this same practice, but the equipment was a huge compressor. When I say large, it is about 25′ long, 12′ tall, and 8′ wide. To isolate this compressor, 38 isolation devices and locks are needed. For years, the facility had used the cable practice successfully, which saved them a lot of time. There were 37 locks for use on other equipment that were also being worked on during the SD/TA.
But here comes a contractor along to mess everything up (poor joke!), and when it came down to it, the facility (and I) realized the contractor did NOT violate LOTO when he cut the cable. Think about it… he cut a cable…
Unfortunately, I am not allowed to share the pictures. Still, the company is allowing me to share what we have learned in the hopes that it will cause others to have this difficult discussion regarding historical LOTO practices in the process industries.