The fumarole. The miners direct the flow of gases through iron pipes to the edge of the fumarole so the sulphur will condense where it can easily (easy being a relative term) be collected. It makes a nice photo, but the workers have to go close to those gas clouds.
Sizing up the task. A miner with a huge load of sulphur (around 100kg) assesses the climb he is about to commence. If it wasn't for the toxic atmosphere, this job would be good training for olympic weighlifting. Unfortunately, carrying that sort of weight will inevitable break bones - sooner or later.