TACTICAL USE OF FIRE HYDRANTS.

That generally is true, about using a 35 ft. 5" feedline/supply line to the pumps, can give good water. The reason for the hard Suction is for Drafting or other situations where a negative pressure, such as low hydrant pressure at a major fire. or when the Engine Company tries to pump to too, many lines or large lines and the Intake Pressure falls below normal. The Hard Suction will not collapse under negative pressure. I have been are major fires in the summer when civilian opened too many hydrants for cooling purposes and the Hydrant Pressure drops. Undersized water mains supplying the Hydrant system can also cause low Intake Pressure. Captain Bob Rainey FDNY Engine 26 retired.
 
captaindewey50267021@gm said:
That generally is true, about using a 35 ft. 5" feedline/supply line to the pumps, can give good water. The reason for the hard Suction is for Drafting or other situations where a negative pressure, such as low hydrant pressure at a major fire. or when the Engine Company tries to pump to too, many lines or large lines and the Intake Pressure falls below normal. The Hard Suction will not collapse under negative pressure. I have been are major fires in the summer when civilian opened too many hydrants for cooling purposes and the Hydrant Pressure drops. Undersized water mains supplying the Hydrant system can also cause low Intake Pressure. Captain Bob Rainey FDNY Engine 26 retired.
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Don’t know if this is in the books for Engine operations or not but, I remember reading or hearing something that Engine companies responding on second alarm or greater could only use the hard suction when they hooked up to avoid exactly what you described.
 
That is a fact. I think it is still so, that FDNY Book of regulations Requires units arriving on 2nd or greater alarm, MUST us a 4 1/2" (Now Normally 5") ridged Hard Suction. I still think that the FDNY Book of Regulations states that the 1sd due Engine on the 1srt Alarm can use inline pumping if Necessary or 3 1/2" semi ridged connection or of cause the Hard Suction. All this is to prevent the Supply line or Suction Line form Collapsing if the Intake of the Engine Co. drops to a negative or close to negative due to low hydrant pressure, or the Engine trying to supply more outlets than the G.P.M. of the water Entering the pump. This can be a real problem anytime, but the situation is even greater when many units are taking water from, the same water mains at a major fire, or in the Summer when hydrants are illegally open by civilians. FDNY Engine Operations also states the same concepts as well as some FDNY All Unit Circulars. Captain Bob Rainey FDNY Engine 26 retired. FDNY Black Out July 1977 Thruxton St. 5-5.jpg
 
captaindewey50267021@gm said:
That is a fact. I think it is still so, that FDNY Book of regulations Requires units arriving on 2nd or greater alarm, MUST us a 4 1/2" (Now Normally 5") ridged Hard Suction. I still think that the FDNY Book of Regulations states that the 1sd due Engine on the 1srt Alarm can use inline pumping if Necessary or 3 1/2" semi ridged connection or of cause the Hard Suction. All this is to prevent the Supply line or Suction Line form Collapsing if the Intake of the Engine Co. drops to a negative or close to negative due to low hydrant pressure, or the Engine trying to supply more outlets than the G.P.M. of the water Entering the pump. This can be a real problem anytime, but the situation is even greater when many units are taking water from, the same water mains at a major fire, or in the Summer when hydrants are illegally open by civilians. FDNY Engine Operations also states the same concepts as well as some FDNY All Unit Circulars. Captain Bob Rainey FDNY Engine 26 retired. View attachment 48172
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Thank you !
 
t123ken said:
I seem to remember reading in the books that that assuming pressures are equal, the 35-foot 5 inch connection delivers more water to the pumps, even more than the hard suction.
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But 35ft 5" connection will collapse if the hydrant pressure gets too low at a major fire or water emergency situation in the summer. Yes, the hard suction is harder to position and use, but it has advantages as I said when water pressure is low, or water mains are small.
Captain Bob Rainey FDNY Engine 26 retired
 
The hard suction has been taken off all pumpers since advent of 2,000 gpm pumps, standard suctions are 3 6” suctions for drafting only. Then the larger soft suction for hydrant 11’ in length but bigger interior diameter than previous soft suctions carried 4 1/2 threads. Next option is 5” 35’ yellow banana and finally the 50’ 3 1/2” for hydrant hook up. Pictures of chauffeur side show this setup, upper 3 troughs have 6” suction hoses, lower trough has the newer soft hydrant connection. Yellow banana is usually in front bumper and the 3 1/2” is either in tray under pump panel or preconnected to gate and stored under soft hydrant trough by straps. I’m not sure if regulations were ever amended regarding hookup via hard suctions on second or greater alarm.
 
3 hard suctions are still on FDNY 2,000 GPM pumpers. As I said when the hydrant pressure drops too low anything, but a ridged hard suction will collapse inward on itself. I have been at major fires when this has happened, especially in Getto areas, during the hot summer days when people open too many hydrants for cooling purposes. The other times it can happen is in times of "civil unrest" when a given area may well have multiple fires in close proximity to each other, that too drops the water main pressure and therefore the pressure available at the discharge outlet of the hydrant/s. The supply hookups you mention have value but not when the pumper intake press reaches about 10 PSI or Below. In the FDNY the exceptions to the rules above are during "Emergency Command Procedures" during period of civil unrest. The need to hit the fire fast and hard and be able to leave and get away quickly if unit/s are subject to physical attack, often requires the use of Inline Pumping. I know I have been there especially in the 1977 "Great New York Blackout". I was a member of FDNY Tower Ladder 18, at that time, and we responded to 7 major multiple alarm fires, in less than 20 hours all of them under Riot conditions.
Captain Bob Rainey FDNY Engine 26 retired.
 
again not looking to argue but the upper three suctions are draft only with 6” threads used for officers side draft port on the 2,000 gpm pumpers. The old traditional hard suction is no longer carried. The old soft hydrant connection was changed with an increase in its diameter and it is more rigid than old smaller diameter.
 
When i was a LT in 332 the then new 1987 Mack Pumper came with an extra wide front bumper with 2 cutouts... one was for the Yellow 35' Suction which not all the MPO's used ....as there was no bracket for the Soft Black Suction it was folded in half & carried in a side compartment....after awhile the covering started cracking where it was folded....later on the Shops added a tray on top of the compartments for the Black Soft Suction.....the other cutout was for a pre connected 1 3/4" in place of the former Booster Reel. 1742785447102.png
 
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