In 1987 I changed jobs.
1. Job I moved from, smoking was fairly common at your desk, and just generally throughout the building. Like racism and homophobia, it was the olden days, before it was bad. Drawing office clerk was generally puffing away throughout the day. While he was on holiday, an enormous fat slob of a draughtsman was working for us on contract, and he took over the clerk duties for a week. Part of his slobbiness was a particularly slurpy, sloughing smoking: both noisy and stinking. Our master drawings were transparencies, suspended from pegs in a cabinet. It was a rite of passage for new graduate engineers to dump all of the masters on the floor due to not being familiar with the cabinet's operation, giving the (usual) clerk an opportunity for explaining the contrast between himself and the unfortunate youngster: "You've got the education, but nae brains!" He would then make a show of explaining how the masters had to be reinstalled, then making the engineer do that, then standing over the engineer, instructing him in minute detail as he extracted the actual master he had originally wanted.
When slobby guy was in charge of the cabinet, about 2 inches of vertically-hanging masters suddenly sustained a brown burn right through them. Probably upwards of 100 drawings. Obviously a single lancing with a hand-held fag. He was completely unrepentant and wouldn't admit it was him: "Could have been anyone! Could have happened at any time, before I started here!" But we knew it had happened that week, and the only remaining smoker in the area smoked a pipe (while working at a drawing board - which also seems incredible now).
2. Job I moved to had smoking permitted in most places; but despite that, smokers would take regimented smoke breaks, either at their desks or anywhere that they felt like it, and no one seemed to think that there was anything wrong with that. It was the entitlement that baffled me at the time, as it still does in retrospect.