I can back the 538 and Car Talk ones previously mentioned.
In the realm of the sciences one that I like that only had a few shows was "Catastrophe" by Jess Phoenix. She's a geologist/volcanist who in the show looked at various things like oil rig explosions, plane decompressions, etc. The human error, design flaws, and other decision making issues that lead to the catastrophe.
It's not the highest quality of podcast and the show is only like 15 episodes or so, but it was enjoyable to me.
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Craig Smallegan P.E., M.ASCE
Design Engineer
Leesburg IN
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