Hehe, always the "wise guy". Can I meet Francheska before you repost? How'd the training go today, and yes I could use you for flashover on Tues.
Jason, the subjectiveness you refer to is directly related to training. My crew was convinced that the sb would not be near as effective as the fog. When we practiced with a sb for the first couple of times they started to buy in to the versatility of it. Once they made their first couple of fires with a sb I couldn't find the fog nozzle to practice vapor dispersion with anymore. I'm pretty sure it's on the rig somewhere. How many do you typically respond with on your engine?
If you get a grant, let's make sure it's for a few million so we can go to some tropical climate during the winter and do the empirical research over cold frosty beverages. But only after burning stuff up all day long of course.......gotta "keep a fire in your life" as a friend of mine likes to say.
I think one concern with boosting the pressure using a pumper is that you still have the other issues relating to fog nozzles and smaller hose diameter. To attain the GPM of a 2.5" (be it 1 1/8 or 1 1/4" tip) the FL on an 1.75" line would be very high again taking the nozzle pressure back down. Not to mention the fog nozzle clogging. Given some 1.75" hose (Ponn @ 1.96") and a smoothbore this may be less concerning but still not the best weapon in our arsenal. My thought given our poor staffing, is if we're going that far from the engine lets take our best offensive weapon to start, 2.5" and dual SB tips. I'd take the Vindicator if not for the clogging issue.Just curious. I haven't heard anyone talk about boosting the building pressure with FD pumping apparatus to overcome the low pressure problems everyone is talking about.There is alot you can do.There should be at least 50 psi more available in alot of cases by doing this. That is unless there are PRV's at the standpipe outlets that are set low.
Paul Shapiro said:
I'm sure many pressure problems could/can be fixed. The problems I have ran into more then once is when I have raised the pressure a failure of some part of the system occured, especially with combonation systems. Each of those times the pressure increases were done slowly and within the supposed limits of the system. It's amazing how much water can come out of a 1/2" pipe, it can flood an entire floor in just minutes. And seeing the basement of a high-rise filling with water is quite demoralizing but I digress.
The debris issue is my major concern and I fear that a raise in pressure could only cause more junk to flake off the pipe. Your thoughts?
I must admit we do not have many standpipes to deal with and none with PRV's so pumping them is clearly an option. Only a few of the systems are new enough to require the 100 psi standard, but none are so tall that a full stretch from the hose bed is out of the question either, though staffing is pretty slim. As you note the First Interstate fire and I'm sure hundreds of others have been fought with smaller lines and fog nozzles, but again in my mind, with any fireground operation, the fewer potential pitfalls the better. Preplanning is certainly key for a FD such as ours where this type of operation is nearly theoretical due to small percentage of systems. But proper planning, equipping and training is our best chance at success.Point taken Adam. I am not talking about replacing 2-1/2" flows with an 1-3/4". Forgive me if I sounded like that was what I meant. All I am saying is that if a building has pressue restriction problems causing FD's to take up larger and heavier hose for every size fire,big and small, then why not use the FDC which is provided to allow FDs to boost the pressure. to give an extra boost that could help. Earlier the First Meridian fire was mentioned as a low pressure problem fire which was caused by Faulty PRV valves creating residual pressures of 30 psi. Exellent case for the 2-1/2" with the smooth bore even for 1-3/4" flows.Boosting the system pressure with FD support would not and did not help at least to my knowledge.But what if the same 30 psi residual pressure was caused by a low system pressure in a building with no PRVs. The same low flow problem would present but this time a boost from the FD would have a good chance of rectifying it.In my years of working with highrise stuff I have learned to take each property as a unique problem and deal with it accordingly. Can you say preplanning.
Perhaps you are right about the age of the buildings, I've been a strong advocate for the procedures you teach about standpipe buildings and use your work as a reference often.