Stretching a hoseline dry to the drop point is a real time saver and reduces stress dramatically.
A good engine company knows how to get a line into operation very quickly while at the same time providing for the safety of firefighters.
While the length of the hose stretch may vary from a short distance to several hundred feet, certain basic principles apply.
- The right diameter line must be chosen
- The correct amount of hose must be stretched
- Stretching a hoseline without water is many times easier than stretching a hoseline that is charged
The Right Weapon For The Job: 1 3/4 vs. 2 1/2
No matter what the situation is, the engine company must deliver the needed amount of water for the task at hand. Smaller fires may be well suited to the use of 1 3/4-inch hose while larger fires or fires in standpipe-equipped buildings are more suited to the use of 2 1/2-inch hose.
The 1 3/4-inch hoseline has the following characteristics:
- Good maneuverability - This can be viewed as an advantage for the limited staffed company. Unfortunately, this mind set may set the engine company up for failure as many times this line is stretched for situations that demand a larger line.
- Moderate flows of close to 200 gpm in stretches of up to 300 feet - Larger rates of heat release demand more water that cannot be delivered from a 1 3/4-inch line. In addition, a longer stretch will require more friction loss to be compensated for.
The 2 1/2-inch hoseline has the following characteristics:
- Fair maneuverability - The 2 1/2-inch handline is a fantastic tool when used aggressively. It is more than a line for defensive operations and can offer a lot of firepower when advanced offensively. The key here is to team up multiple engine companies to get a single line in operation. By teaming up engine companies, a 2 1/2-inch line can be moved very quickly, but the key is placing firefighters at each friction point or "pinch" point.
- Excellent water flow - Equipped with a 1 1/4-inch smoothbore nozzle will allow the engine company to flow 325 gpm. High flows can also be achieved with the newer low-pressure fog nozzles. Friction loss is also much less than using the smaller 1 3/4-inch line with the lesser flows.
Pre-Connected Lines vs. Bulk Hose Beds
The pre-connected line is not suitable for all stretches and an engine company should be equipped so as to get a line into operation at building fires where the "preconnect mindset" would cause ineffective hose stretches. A solution is 2 bulk hose beds with:
- 600 to 800 feet of 2 1/2-inch attack line with a high flow nozzle (1 1/4-inch smoothbore/325 gpm or a high flow/low pressure fog nozzle.
- 200 feet of 1 3/4-inch hose to a reducer to several hundred feet of 2 1/2-inch hose. This allows for 1 3/4-inch hose to be placed into operation many hundreds of feet from the engine, but without excessive friction loss. (see Figure 1)
Stretching the proper amount of hose is critical. Here are basic rules of thumb from two exceptional chief officers. Obviously, there are always variables that can alter the amount of hose needed, but these are a good place to start.
- From William Clark's book Firefighting Principles and Practices, 2nd edition (Page 266, Penn Well Publishing, 1991), the author estimates one 50-foot length for each floor up to and including the fire floor, plus an additional length, plus the distance from the engine to the building entrance.
- For commercial occupancies, from John Norman's book Fire Officer's Handbook of Tactics, 3rd edition (Page 51, Penn Well Corporation, 2005), the author calculates the length of the building's frontage plus the depth of the building to estimate the amount of hose needed, plus an additional length for every additional floor the company must stretch to, plus the distance from the engine to the building entrance.