1660604335515 Cd1005 Learning

Learning the Hard Way

April 28, 2010
Learn from Experiences Is One Way to Learn. However, Most Lessons Derived from Experience come with a Bitter-Sweet Taste

By Joe Feeley, Editor in Chief

This month, our cover story (Safety to Operate) updates us on the progress of integrated safety and machine controls in our industry. Given that today's well-designed safety systems allow machines and production lines to operate more productively with less downtime and less risk of operator injury and machine damage, anything other than solid progress along these lines, regardless of the economic climate, would be disappointing.

Related item that makes you appreciate the value of unshakable safety urgency: This made me cringe. Repair technicians inadvertently disabled the train-crossing gate system of an active Chicago-area commuter track on April 17. A fast-moving train T-boned a car as it crossed the apparently safe and clear track, killing the 27-year-old driver. The technicians apparently had been repairing some switch signals.

No one is talking much on the record about this right now, but The Chicago Tribune reported that the ongoing investigation indicated the track-crossing-protection system unintentionally was turned off by a maintenance crew that was installing an interlock that controls track switches and train movements in this type of track configuration.

It's been theorized that the track switches and the gates shared a power supply, so taking down the switch circuits took down the crossing gates.

Whatever turns out to be the reason the tragedy happened, and I'm guessing it won't just be because somebody didn't follow procedures, it's beyond me to think that today a system could be designed and installed that doesn't default to an abundance of red stop signals and warnings along the train track if something that critical is not right.

The Federal Railroad Administration has some data that notes there had been five train-car crashes at this crossing since 1991 before this crash.

If this doesn't put a giant exclamation point on the need for the highest level of safety system design review and risk assessment, I don't know what does.

This is the equivalent of disabling the access controls on a manually loaded and unloaded hydraulic press in a way that the operator couldn't possibly know he wasn't protected.

Impossible, you say? That's what I would have said about the train crossing.

Is training an issue here? The best hands-on, how-to training can fall short, sometimes in devastating fashion, if it doesn't include both an appreciation of the overall system and a system that compensates for errors in judgment or planning.
I hate to second-guess these things, but when something goes this wrong, all bets are off.

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