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Comment by calgarymicro | Hacker News Reader

The USCSB didn't just recommend labels in that case (though that likely would have prevented the incident since it was caused by someone unfamiliar with the facility who might have read them). They also recommended making sure the connectors for the inlets were different so it would be physically impossible for the error to occur.

That said, it's quite silly indeed that the inlets for two incompatible chemicals that would release toxic fumes if mixed were 18 inches apart, unlabeled, used the exact same connector, and were locked behind the same gate. I don't think it takes extraordinary collective intelligence to see how this could become a problem.

The report for anyone who wants to know more: https://youtu.be/Tflm9mttAAI

I don't recall the compound gate thing but I'd appreciate a link if you have one.

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The inlet valves had separate locks on them, and presumably the plant worker was supposed to unlock the correct one for loading - but on that day both were left open for some reason.

Yup, so I guess I'd add that to the list - careless management of the padlocks for the valves, in addition to the gate, labeling, connector, and placement issues.

Oh my god they locked away their safety equipment too?

> mixed were 18 inches apart, unlabeled, used the exact same connector.

They were labeled.

Same connector - Standardized connectors are safer. Every chemical can't have a different connecter. If the truck swaps connectors in and out per location you are mostly back to square one.

The connectors were locked, that's the differential they choose. Except one wasn't, which is the same issue as the truck swapping connectors. It shouldn't have been possible to have two connectors unlocked at once.

> were locked behind the same gate.

Multiple gates creates other issues.

> 18 inches apart

This the problem, multiple gates a distance apart are an issue, but probably the solution. It also allows clear signage on the gate rather than than the 7 characters you can see on the connector label. I count 5 - 7 connections, they can't all be behind a gate, so there is no hard rule.

> compound gate thing

https://www.youtube.com/watch?v=jh2HWT8gPeY

They actually want a 'written' policy to stop people coming in. People ram raid gates to get into compounds so they can't be flimsy. In an emergency power could be out and you can be in a car or running while on fire.

> They were labeled

Were they? It says they had labels some distance down the pipe, but they weren't labeled at the point where the hoses connected where someone could actually read it.

> Every chemical can't have a different connecter.

Every chemical doesn't have to have a different connector. Maybe just ones that will cause a dangerous reaction if mixed.

> I count 5 - 7 connections, they can't all be behind a gate, so there is no hard rule.

Sure. Again, a good rule of thumb would be to separate the ones that could cause rapid death.

> They actually want a 'written' policy to stop people coming in.

So no fire code issue then.

> Every chemical doesn't have to have a different connector. Maybe just ones that will cause a dangerous reaction if mixed.

The issue is that they're buying chemicals from vendors so they don't necessarily have control of what connectors are on the truck. If you have Bleach in connector A and acid in connector B, you better hope they don't send an acid truck with an A connector.

I think having a way to close the fill lines remotely would have at least seriously downgraded the problem.

I doubt every chemical facility uses the same style connector, so at some point in time this information would have had to be communicated to the chemical supplier anyway. And sure, the supplier could just happen to send the truck with the exact right connector for the other chemical (though that wouldn't be a problem if they just moved the inlets apart), but that's a lot less likely than a screw up when the connectors are the same. I'm not saying (and I doubt the CSB is either) that any of this would eliminate the possibility of incidents. The point is that they'd become much less likely.

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