safety

Software Safety

Posted on by Cheryl Rofer

If you supervise people moving quantities of soil and debris with big machines, or people doing things with plutonium in glove boxes, questions of safety quickly become important.

Software developers have been much less aware of safety issues. What can go wrong besides lacking an ergonomic chair?

Social media sites and “AI” development are beginning to highlight safety in software. I’d like to throw out a simple principle that the software people might like to think about.

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The Ohio Train Derailment

Posted on by Cheryl Rofer

On February 3, a Norfolk Southern train carrying hazardous materials derailed near the town of East Palestine, Ohio. Fifty cars derailed, ten of which carried hazardous chemicals. Federal investigators say a mechanical issue with a rail car axle caused the derailment.

A fire broke out in the rail cars, residents were evacuated, and the material in some of the cars was drained and set on fire. Draining the material prevented a BLEVE, a boiling liquid expanding vapor explosion, which is what happens when tanks of liquid are heated in a fire. A breach in a hot tank like this releases both chemical energy when the liquid explodes and the heat energy as the liquid flashes instantly into a gas. These explosions are extremely powerful.

But then they had to do something with the liquid, so they burned it, producing a thick black cloud of smoke.

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What Went Wrong

Posted on by Cheryl Rofer

On June 30, the Los Angeles Police Department detonated fireworks in a containment vessel mounted on a vehicle. The resulting blast damaged cars and houses and injured people. Sahra Sulaiman has been covering the blast and subsequent events. She has summarized the events around the blast.

I’m always intrigued by reports of explosives gone wrong. I worked with scientists in the explosives division of the Los Alamos National Laboratory, in their laboratories, on a chemistry project that did not involve explosives. In order to do that, I had to have training on explosives safety. Additionally, because people who decide to make their career in explosives love explosions, I was invited to observe a number of explosions.

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