Earlier quoted context omitted.
The Wikipedia article the previous commenter linked doesn't mention this, and I've looked at a few sources linked from it and they don't mention it either. They mention that previous Therac machines had "hardware interlocks" to prevent this sort of issue - maybe those are the safety fuses you're both talking about? - but it says they were never included in Therac-25 in the first place, because the software was assume…
Yeah, the lack of hardware interlocks are part of what makes it a (literal!) textbook case for software engineering ethics. I remember talking about it several times over my college career, and for good reason. To this day when people start talking about software in the loop in a safety context I get extremely twitchy. I don't let that shit happen on my watch.
Today, I’d ask about more ways to push the responsibility away from the firmware to stop catastrophic failures. If the debugger pauses the CPU you can’t use the CPU to regulate things. I’ve worked on things where the failure mode can be explosive and it makes dev really harrowing if you can’t rely on hardware interlocks.