Coal-mining
Ironworks and steam engines needed coal. As they spread, the demand for coal grew. So more mines were opened, and deeper shafts were sunk. Deeper pits meant more danger for the miners, above all from water and gas. An explosion at Felling pit on Tyneside in 1812 killed 92 men and boys.
Inventors tackled the problems, but only partly solved them. The steam engine helped with the pumping. Using two or more shafts produced a flow of air and better ventilation. Sir Humphry Davyīs safety lamp (invented in 1815) reduced the risk from gas.
In Scotland the mine-owners employed women and girls as well as men and boys. (Their wages were lower than menīs.) Inspectors in the 1830s found pits where boys and girls of four or five sat for hours in the dark, opening and closing trap-doors. Their report shocked the public. In 1842 Parliament passed a law which said that girls, women, and boys under ten could not work underground.
Walter Robson: Britain 1750 - 1900; Oxford University Press, 1993, page 17 f.