I collect old highschool social studies and science textbooks. Few journals can more accurately depict a time period than these. As an example, when Madeliene Albright described waiting out the Blitzkreig as a child in a London basement, she expressed little chance of surviving a near-direct hit due to the many underground pipes exposed in their shelter. Steam was cited as the worst latent killer should the pipes rupture.
When I got home, I dove into my collection. There I found a diagram of London's underground utilities in Popular Science Mechanical Encyclopedia, 1941. Talk about a "direct hit"—I couldn't have nailed it any better. Young Madeliene had everything BUT steam to worry about. Consider compressed air and pressurized hydraulic oil at 700 P.S.I.
How thoughtful it was for the city to provide these resources where one could plug their hydraulic wood splitter into a coupler in a back alley and split wood without the engine noise. Moreover, one could inflate a soft tire at selected street corners. In addition, there were 4 water mains, 4 gas mains, and two high voltage lines. Exposure to these utilities could indeed be fatal along with a "foul sewer" adding insult to injury.