The job I have now. Well its a lot better now than it was 6-7 years ago. I work in a casting plant of a refinery and its regularly over 40 degrees ambient temp in the building, then it just keeps getting hotter when you work next to all the LPG burners and metal furnaces. Along with that we had to knock the lifting pins out of the 1 tonne blocks we make with a sledge hammer. 2 pins per block and the pins would stick badly so we had to hit them, full swing, 6-8 times per pin to get them out and we did that to 185 blocks per shift. Back and hands were killing at the end of each day. The other machine made smaller 25kg blocks and it would regularly run very poorly so we'd end up picking up 10-15 tonnes of these blocks off the floor each shift and loading them into bins. During summer, a lot of blokes would be on their knees at times from fatigue. And it's not just me being a whinger. In 2012 we had 93 blokes, out of a workforce of 280, quit due to the conditions. Things are slowly getting better and more machinery automated.
But I cant complain as there are many out there who have it far worse than me.