Engine companies, also known as pumpers, carry hose to facilitate fire suppression and extinguishment. This is accomplished by connecting the soft suction hose from the pumper to a fire hydrant. This takes water from the water main and supplies the fire pump inside of the pumper truck. The pump builds up pressure that pushes the water through the fire hose and gives the fire stream velocity or speed in order to reach the fire. The primary function of an engine company is fire suppression.
At the rear of the apparatus is a flat space referred to as the hose bed. The hose beds on Skokie Fire Department engine companies are divided into three sections. The left and center hose beds carry 550 feet of 3-inch hose. On the left bed, a pipe or nozzle is attached. This known as a "big line" is used to attack heavy volumes of fire or for exposure building protection.
In the center bed, 100 feet of smaller 1 3/4-inch hose is attached to the 3-inch hose. Again, at the end of this hose is a nozzle. The nozzle on a fire hose shapes the stream to assist in its reach. This line is usually used on smaller residential or automobile fires.
On the right side, 800 feet of large diameter five-inch hose is bedded. This hose is used to supply large volumes of water for master stream devices at major fires. Master stream devices include multiversals, deluge guns, aerial pipes and tower ladders. The 5" hose is also used for inline pumping (water relay) and quick water evolutions.
On either side of the pumper, directly behind the cab of the apparatus, are preconnected hose lines. Called "preconnects" or "crosslays" these 200-foot lines are used primarily for residential or automobile fires. They are used in conjunction with the 500 gallons of "tank water" carried on the apparatus.
If the onboard water supply is insufficient the officer may elect to use a "quick water" evolution to supply the hose line before the tank water supply is depleted. A second choice may be to have the second due engine drop the first engine a "supply line." Also carried on the engine are 30 gallons of foam concentrate for flammable liquids fires.