"Little House on the Prairie" has a scene where the father digs a well and tests the air downhole with a candle. That's awareness of the danger in a literary work more than 100 years ago. Farmers and well-diggers have been aware of the phenomenon for centuries, it's inconceivable that a fireman of the mid-20th century didn't know how to defend himself against the danger.
it's inconceivable that a fireman of the mid-20th century didn't know how to defend himself against the danger
Not as much as you might think. Firefighters routinely fought fires without SCBA up until at least the 70's, and probably into the 80's in rural areas. And if they weren't using SCBA for structure fires, they probably weren't using them for rescue calls in most cases. It was a cultural thing... for a long time, firefighters just didn't understand/appreciate the importance of SCBA. In hindsight that seems hard to believe, but it's been a slow process to get to a place where every firefighter is rigorous about making sure they use SCBA at all required times. (To some extent, that could be said about other protective gear as well, including turnout gear and PASS alarms).
Also consider that many (probably most) fire departments don't receive a lot of specific training on confined space rescue. Of course, you might ask, "why not?" and the simple answer is "time". Especially with volunteer firefighters, you can only get folks out for so much training a week. And fire calls are many times more common than confined space calls, so most training time is spent on the routine firefighting stuff.
Similar thing with hazardous materials training... it's a relatively recent thing for the majority of fire departments to receive specific haz-mat training, and even then, unless the department runs a specialized haz-mat team, their personnel probably only train to the "awareness" level.
I don't mean to excuse the fire chief, as I don't know the details of that specific story. But for something like that to happen, especially that many years ago, isn't a complete surprise.
Source: I was a firefighter and certified firefighting instructor throughout most of the 90s / early 2000's. My dad was also a volunteer firefighter and I've had a lifelong interest in the fire service.
