Glossary of Firefighting - D

D

• Dalmatian: "Firehouse dog."
• Dead lay: A load of hose on a pumper, but not connected to a pump outlet. Often used for larger supply lines.
• Defensive Attack: A primarily exterior form of attack often used when fighting the fire directly or from within a structure is not feasible due to dangers from direct flame, heat, structural collapse or the presence of hazardous materials. Often structures which are fully involved are attacked defensively with the main goal being the protection of nearby exposures. This form of attack is far less effective than an Offensive or Direct attack. Also known as "surround and drown."
• Deflagration: An explosion with a propagation front traveling at subsonic speeds, as compared to supersonic detonation.
• Denver Drill: A drill that essentially re-creates the rescue of Denver firefighter Mark Langvardt. It incorporates the use of a leveraged body and an inclined plane (bio-mechanics) to get a victim up and out of a narrow window in a narrow hallway (the Denver Prop).
• Denver Prop: A training prop designed after the actual dimensions of the confined area that claimed 16 year veteran fire fighter Mark Langvardt's life in 1992. Specifically, it is a 'hallway' 28" wide, 8' long with a window at one end that is 20" wide by 28" high and the sill is 42" from the floor. The prop is used for the Denver Drill.
• Direct attack: "Putting the wet stuff on the red stuff." A form of fire attack in which hoses are advanced to the fire inside a structure and hose streams directed at the burning materials.
• Discharge flow: The amount of water flowing from a fire hydrant when it is opened; compare to static flow and residual flow.
• Determinate A code given by dispatch (Alpha -Echo) showing the severity of a call and how you should respond.
• Dispatch: Refers to person or place designated for handling a call for help by alerting the specific resources necessary.
• Draft: The process of pumping water from a static source below the pump.
• DOS: Death On Scene.

• Drills: training during which an emergency is simulated and the trainees go through the steps of responding as if it were a real emergency.
• Drop Tank: A portable tank used at fire scenes to store water from Tenders for Engines