A "firefighter" that ,for some unknown reason, begins breathing air from his/her SCBA while in the fire apparatus, while en route to a fire call. These individuals are then automatically reclassified as "Yard Breathers" once they exit the fire apparatus. See definition for "Yard Breather"
That Johnny is a damn Engine Breather, look, the trucks not even on scene and he's breathing air
by Fraternal Brotherhood of Salt October 29, 2010