Spotting the First Engine at a Garden Apartment with an FDC on the Charlie Side
You are the officer on Engine 4, first to arrive at a 3-story, 12-unit wood-frame garden apartment, 180 ft long. Fire is showing from a second-floor balcony on the Alpha side. The building FDC is on the Charlie side, about 90 ft from the corner. The nearest working hydrant is 260 ft past the far end of the building on a 6-inch main. A hydrant directly in front of the building is bagged out of service. A truck company with a 100-ft aerial is two minutes out. The street is 26 ft wide with cars parked along the Charlie curb; overhead lines run along the Alpha side. Engine 4 carries 500 ft of 5-inch and 800 ft of 3-inch supply line and has a 1,000 gpm pump.
1. Where do you spot Engine 4, and how do you lay out supply and attack lines? Defend the choice.
Read the worked answer
Spot on the Alpha side, past the involved unit, leaving the front of the building open for the aerial.
Reasoning:
- The fire is on Alpha; a short, direct attack line from the Alpha side is the fastest way to put water on it. Stretching from Charlie around the corner wastes time and hose.
- Spotting past the fire keeps the apparatus out of the front elevation where the truck will set up and where the aerial will need room for outriggers.
- Do not use the bagged hydrant. It is out of service, and connecting to it wastes the most valuable minutes on scene.
- The working hydrant is near where you are spotting, so a short 5-inch connection serves you. The FDC on Charlie is roughly 150 ft away around the corner (90 ft plus the corner run); a 3-inch line reaches it.
Caveat on the FDC line: if the standpipe demand is high (500 gpm or more), a 150-ft 3-inch line has substantial friction loss. In that case a second engine should take the FDC with 5-inch, or you should use 5-inch to a wye. Say so on the radio rather than quietly accepting a weak FDC supply.
2. The truck officer asks you to move 30 ft forward so the aerial's outriggers clear the parked cars. What do you consider, and what do you do?
Read the worked answer
Do not move a charged engine casually.
Considerations:
- Moving breaks or drags the supply connection and the attack line; crews inside lose water at the moment they need it.
- Moving 30 ft forward may put the engine into the intersection, blocking access for later-arriving units and the medic.
- The aerial has alternatives: setting up slightly farther back and working at a different angle, using the Charlie side, or using ground ladders for the second-floor balconies.
- The parked cars are an enforcement problem: request police for towing or relocation, which may be faster than re-spotting.
Decision: if the move is truly required, it must be done deliberately: notify the crews, shut down and drain the affected lines, move with a spotter, re-establish supply, and re-charge. If the aerial can work from its current position at a safe angle within its load chart, keep the engine where it is. A 30-ft gain for the aerial is not worth a water interruption unless the aerial cannot reach the objective any other way.
3. How do you confirm the hydrant can supply the FDC and attack lines, and what do you do if it cannot?
Read the worked answer
Test it while flowing, not while static.
- Record static pressure with the hydrant fully open and no water moving.
- Flow the lines or a test stream and read residual pressure at the same time.
- A drop of roughly 25 percent or more from static to residual signals a hydrant that cannot give much more. A residual that falls to about 10 psi or lower while you are flowing is a warning that the main is being drawn down.
A 6-inch main is normally adequate for a moderate fire, but it depends on the grid, the distance from the source, and whether it is a dead end. If residual collapses:
- stop adding lines and tell command the supply is limited;
- use the engine's tank to supplement while a second hydrant or a tanker shuttle is established;
- consider laying 5-inch to a better hydrant rather than trying to force more out of this one.
Report the numbers to command. Do not wait for the stream to fail before acknowledging the limit.