Sprinkler Hydraulic Plate (Sign Placard) information

[JCianfarra]

Hello Forum,

re: Sprinkler Hydraulic Plate (Sign Placard) information

I have seen a lot of confusion regarding the information on a fire sprinkler hydraulic plate. The address placed in the "location" slot instead of the remote area location, total number of sprinklers instead of number of sprinklers calculated...etc. For the information regarding flow and pressure at the "base of the riser", I generally see the system at the source instead of at the base of the riser which is a real point of confusion and the hose may or may not be added.

My question is also about the last item. When filling in the information about the "Residual pressure at the base of the riser", should I be considering water pressure before or after the fire pump? Most of these questions can be answered my asking who actually uses the hydraulic plate and what do they do with that information.

Thanks, Joe Cianfarra

 

[cdafd]

http://www.eng-tips.com/viewthread.cfm?qid=340886

 

[JCianfarra]

cdafd,

Yes you are correct with your linked reference to the post that talks about those other issues I initially referenced. Are you implying that I should include my query there as well for them to see since those members obviously were interested in this topic?

Thanks,

Joe Cianfarra

 

[cdafd]

No
Knew that a similar question had came up and there were replies

 

[JCianfarra]

Yes it is similar, regretfully it is a closed thread so I can't add my comments to it, however hopefully somebody interested in expanding the discussion sees this one!

 

[cdafd]

Not an engineer or designer but wouldn't that be the number from the hydraulic calcs ?

 

[cdafd]

http://www.usfa.fema.gov/downloads/pdf/coffee-break/cb_fp_2012_16.pdf

 

[JCianfarra]

Yes the number(s) do come from the hydraulic calculations. As the Coffee Break article reiterates, "The required flow and residual pressure demand at the base of the riser", and this of course is typically not the number that you find on the cover or an the end of the demand curve. The calculations provide pressure numbers at every single calculation node point. Depending on how far out you run your calculations to the "Supply", the demand number may show the requirements needed a mile away down the bottom of a hill. Adding a fire pump into the equation adds even more variables into the options. Some people calculate the city water plus the fire pump pressure insert this information which creates a combined demand at the pump discharge. Some people insert both the city water data as well as the fire pump data into the calculations where you end up with an ultimate city water demand pressure. As these strings illustrate people are horribly off on what information goes on the hydraulic placard, so maybe I am just being a little anal. I think it is my special hazards background creeping through.

Thanks again,

Joe Cianfarra

 

[PRinspector]

OK, sense we are visiting this topic what would you consider permanent? Will you accept permanent marker?