Fumer comme un pompier, literally “to smoke like a firefighter”, means to smoke a lot. This expression dates back to the end of the 18th century. Before the development of fireproof clothing, firefighters used to wear wool or cotton clothes. These fabrics could easily be ignited, and, for this reason, were sprayed with water. With the intense heat, the water that was sprayed was transformed into steam. When the firefighters exited the fire, it was as if smoke was coming from their bodies and clothes. That image became linked to inveterate smokers!