It takes 2 guys to dress out the one guy in the suit. That “60 minute” cylinder might last that long if you were used to wearing a positive pressure SCBA and sitting in a chair. Working and unfamiliar, it’s going to last maybe 20 minutes.
But it’s a great to sweat off some weight in August!
I worked hazmat for many years. You are largely correct, but we got a lot more than 20 minutes out of our 60 minute bottles. And while we typically did have two people assisting with getting us into the suit. The two doing it would spend a couple minutes on one guy and then move onto his partner. We also used vests with packets of frozen blue goo that lasted about as long as the bottles when it was hot out to help keep us from getting overheated as quickly. But full level A hazmat suits are always a pain.
Typically we used the suits to collect samples, to patch leaking vessels or open and close valves. These are not real labor intensive. Of course occasionally did we have to drag someone out of a hazardous place and get them to our decon area. Depending on the hazard we had to wear a level A suit while doing decon. (decontamination)