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Engineering fire protection systems - Who is responsible? 2

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SprinklerDesigner2

Mechanical
Nov 30, 2006
1,251
I'm a NICET layout technician and I don't do engineering. I lay out sprinkler systems using the appropriate NFPA standards as a cookie cutter.

I am looking at bidding a large project consisting of a fire pump, five standpipes and full sprinklers on every floor. The state where the job is located does not allow manual standpipes and to top it off both the state fire marshal rules and the state EPA requires all fire pumps to maintain a minimum suction pressure of 20 psi @ 150% of capacity.

Drawings and specifications don't have anything pertaining to the size of the fire pump with the exception it have a 125 HP electric motor. Nothing about gpm or psi.

The project drawings are sealed and signed by a registered professional engineer.

I know I can make this work with a 1,000 gpm pump and, while I am not done checking, with a 125 HP motor the pressure would range between a low of 102 psi and 125 psi.

Drawings consist of a plot plan showing an 8" line extending from an 8" city watermain to a little tiny pump house (split case, good luck fitting everything in there with the required backflow assembly) and then lines feeding the standpipe. The extend of the sprinkler drawings are circles where heads are supposed to be.

I attempted to set up a flow test but was told I couldn't because a contractor was working changing out some underground somewhere in the facility and they didn't want surges.

I do have a partial flow test that was given to me by the facilities engineering department that indicates a static of 48 psi and residual of 28 psi flowing through a 2 1/2" hydrant butt. Using a discharge coefficient of 148 for the hydrant it appears we can expect 48 static, 28 residual @ 700 to 800 gpm flowing.

I expressed my concerns in an RFI and received the following response:

"The fire sprinkler contractor is required per the plans and specification to design, provide, and install complete building sprinkler coverage, except for areas noted herein, with automatic wet system in accordance with NFPA 13."

I had a two page RFI detailing my concerns and what is required and this is all I get back?

With five standpipes would it be unreasonable for me to assume the engineer of record checked the availability of water knowing a minimum of 1,250 gpm would be required for the standpipes? Would it be reasonable of me to conclude the engineer knows of the state minimum requirement of having 20 psi at the pump suction flange when the pump is operating at 150%?

My big question is when it doesn't work WHO PAYS for the upgrades to whatever is required (tank?) and the delay in the project that has liquidated damages that would take me out in a couple weeks?

If PE's want to get into fire protection, because there's money in it and times are tough, shouldn't they be required to know what they are doing or can they just toss all the responsibility onto the sprinkler contractor?
 
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First of all, I believe the required standpipe demand is only 1000gpm for a fully sprinklered building. With that said, even with a smaller pump, it appears your supply isn't capable of delivering even the 1000 without dipping below the 20psi.

It isn't unreasonable to assume the engineer did his homework, but in this case it does appear unlikely.
 
ryan,

You're right but in this case the building is not fully sprinkled but it will be when all the phases are over which can take several years. My thinking was to give the 1,250 just in case an AHJ wouldn't accept 1,000 gpm as long as it didn't cost a whole lot which it wouldn't.

Even if I went with a 750 gpm pump what would be my minimum pressure using the specified 125 HP motor?

The 20 psi minimum suction requirement is with the pump operating at 150% not what the demand is so even with a 750 gpm pump I we're looking at 20 psi @ 1,125 gpm which I can't see getting.
 
Consider another RFI to verify the suction pressure, etc.

One point per RFI.
 
Probably a Mechanical Engineer who performed a simple brake horsepower calculation so the Electrical Engineer knew how to size the conductors for the fire pump. He/she didn't look at any NFPA standards.

Put the burden of design back on the engineer.
 
My personal opinion would be to walk away from a project like this.

Where I work (Ohio) the sprinkler contractor is responsible for laying out the system, making sure it fits, running hydraulic calcs to make sure the system works. But he has to be given the flow/pressure requirements of the fire pump to plug into the calculations. He has to be given flow/pressure information from a recent hyrdant test or be instructed to perform one. If the hydraulic calcs indicate the main pressure or system equipment is not adequate, then a change needs to occur (larger pump, tank to store water, etc.) - which should not be a cost to the sprinkler contractor.

When you get idiotic answers to simple questions, it is probably indicative of the type of answers you will get after you have a contract.

It will only be problems of pointing fingers during construction. If you have a GC/Owner/CM who tends to take the engineer's side, you will have problems.

This is from an engineer, not a sprinkler designer, so I am from the "other side".

If I put out a design that had a fire pump and did not give flow rate, TDH, didn't get some flow/pressure information for the supply, determine whether a tank is required due to insufficient main pressures, or did not indicate how many standpipes would be required, I would not have a job for very long.

As I said, I would walk away from a potential land mine.

 
I agree with Pedarrin2. You should run from this one. The underground isn't capable of providing either standpipe demand, 1000gpm or 1250 without going below 20psi. It doesn't matter what size pump you try to plug in. You are most likely looking at a large storage tank to supplement the city supply. If you try to cover all that in your bid, you will invest alot of time and money only to find some other sprinkler contractor missed the problems. They low-ball it and yours gets thrown out. I have seen it many time myself.
 
SprinklerDesigner2,

I don't think you need to run away, as long as your concerns are addressed, in writing.

regardless, this is a perfect case to make this point,

file a complaint against the engineer and their company with the state engineering board, and let them figure it out. If you want to be anonymous, file it anonymous, but file it!.

The ONLY way engineers like this will learn is if they are made to stop. The only way to make them stop, in a self policing profession, is to file a complaint. The engineering board has no idea, and no means of starting to investigate unless a complaint is filed.

Besides practicing engineering without a license, nothing bothers me personally more than an engineer working outside their abilities, outside their area of expertise.

 
firepe,

I am going to bid this project. The job is right "next door", we could use the work and I don't view the water supply as our problem.

A registered PE sealed and signed the drawings which show the fire line tying into an 8" main. Who the heck am I to double guess? I am a nobody, I am a simple technician and I can not imagine an PE would so indicate this line was adequate unless he adequately investigated the issue and knows.

What is a seal and signature worth? It has to be worth something, right?
 
Sprinkleresigner2: I think what you are looking at is a "Performance Specification", which is sometimes commonly used for many projects, especially Fire Protection/Sprinkler systems where things are very "Codified". Basically the Design Engineer is throwing most of the risk onto the sprinkler contractor to design the system in accordance with the Codes. What you have to look at is that in fact that YOU are the one who has to design the system and install it to Code. Unless there are specific requirements in your local building bylaws that require the design engineer to provide complete drawings, hydraulic calcs, cut length shop drawings, etc,. then all the Design Engineer has done is throw the bulk of the design work over to "The Contractor" to do it as a "performance specification".

It avoids risk on the part of the original engineering office that issued those documents, and maybe that's all the Owner/Client paid the Engineer for in the first place, in order to think he saved money. There are no real savings because "someone" still has to do the design work and I'm sure you don't work for free either....
 
SprinklerDesigner2,

As I said, I don't think you need to run away. If we are afraid to take risks, we should not be in business as contractors.

I think you have taken a defendable approach, these specs were not written by you, and you are not an engineer, nor the engineer of record, but rather are acting solely as a piping trade installing pipe according to provided engineered drawings and criteria.

You can use your NICET credentials and code of ethics in your defense and favor as well if any suggestions are made that you are somehow to be responsible for the engineering.

It is then in your court though when you actually run the calcs and cry the sky is falling when you prove what is in the specs and on the drawings does not work.

At that point, forward all of that to the state and let them investigate this engineer.

Good luck
 
SprinklerDesigner2

As for your comment "What is a seal and signature worth? It has to be worth something, right?"

When engineers put in all of that time to go to school, and get their degrees, and take time and trouble to take the exams and get licensed, it always boggles my mind to see those that are willing to trade their hard work and integrity for a few dollars, by blatantly practicing outside their area of expertise.

When that happens, that stamp is not worth the rubber it was molded from.
 
What GMcD said....

If you are bidding the job as the Fire sprinkler "Contractor" and bidding the specs that asks the contractor to design teh ssytem and run the calcs, then you (the Contractor) is responsible for the design. It does not mean that you have to do it personally, you can certainly hire someone to do it and get paid for it. Your bid need to carry that price.

The engineer's response is clear and you can't blame him for it. His response already clarified that he did not do the design. Perhaps he was not paid to do that.

Rafiq Bulsara
 
As previously stated I was not allowed to conduct a flow test and I will clearly qualify this in my bid.

PEDARRIN2 probably knows who I am talking about.

There was once a sprinkler company (since sold to a larger company) that through marriage had more money than God. In 1992 a group of us upstairs designers ran across some private bonding company documents while looking through some older files looking for drawings we needed for an addition. The bonding papers showed his wife receiving $8 million a year from a trust fund. Being an only child when her surviving parent died she would inherit all of what he had and become rich. When sold the company employed between 700 and 800 fitters so it was not a small time company.

Not to take anything away from the man he had a fantastic mind coupled with an aggressive business personality. Sometimes I can't remember what I had for breakfast and this guy never forgot anything. I have little doubt he would be successful in anything he went into but he went into sprinklers.

The company had a very similar job and when told of potential problems his instructions were to bid it exactly as shown on the contract documents.

Of course all the problems came up and the company wanted a lot of change orders. The architect made the mistake of threatening the owner with default, bond etc at which point things got really messy.

Went to court and it took a number of years but eventually the case made its way to the state supreme court to which the owner and his family donated heavily (its public record) to the election campaigns of a number of justices.

The court completely sided with the contractor saying saying it was the engineers seal and signature on the bid documents and he was sole owner of the problems. The architectural firm got hit heavily in their errors and omissions insurance even though the specs stated final design was up to the sprinkler contractor. Word got out and architectural firms in this state completely rewrote the way they approach fire protection systems.

Of course the ruling applies to only one state, our checkbook couldn't handle reimbursing the bonding company for expenses so it wouldn't interfere with our bonding ability and I don't have a million bucks to drop on lawyers.

I wasn't allowed conduct the flow test due to lines being replaced so maybe we have the water. Maybe we have enough to maintain 20 psi with a 750 gpm pump running at 150%. It is possible.

I can't find anything on the drawings or specifications about it being a performance spec.

A relief valve and waste cone is specified along with a 125 hp motor so I have to think the engineer knew something because you can get a lot of pressure on a 750 gpm pump using a 125 hp driver.

I like the way things are handled in South Carolina where the PE and layout technician work together as a team. The PE is responsible for verifying the water supply and writing a specification as to density and hose streams required. I draw the job up and the same PE has to review the drawing (he doesn't seal or sign it) filing a statement he has reviewed the drawing and it is in accordance with the water supply and specification he wrote. This keeps me from having to practice engineering which I clearly recognize I am not qualified to do.

To keep small jobs from being bogged down South Carolina has a limit, I think it is something like 20 heads, that doesn't require an PE's specification and verification sheet.

The longer I do this the more I recognize a review by a knowledgable PE is needed. I am not an engineer.
 
Before you do anything, you must do a hydrant flow test of the water supply to the building. If I remember correctly the minimum suction pressure of 20 psig is established so as not to collapse the supply water main and don't assume that enough water will be available to the pump and still be at or above the 20 psig.
About doing a hydrant flow test upstream from where the lines are being replaced and then calculate the water availabilty at the pump intake with hydraulic graph paper.
With hydraulic graph paper, you can graph water supply, friction losses thru water mains and sprinkler lines, pump performance which you can directly get from the pump manufacturer.You can also do hose line deductions, hydrant deduction and from all that info you can estimate water supply to the most remote sprinkler heads within that building.
 
As I said before, I would not take the job. Too much missing information and lack of engineering on the engineer's front.

It sounds like the engineer is hiding behind a "performance spec" to cover up a low fee or a weak design.

I wouldn't performance spec a pump job with 4 to 5 standpipes.

There are risks in everything - but some risks are not worth it.

It is probably doubtful you have in your bid the price for all the meetings, site visits, phone calls, redesigns, etc. that will be required for this job - let alone hiring a PE to do the design for you.

I do the same thing in Ohio as to review of the drawings and calcs. I stamp it approved or rejected - although the contractor can overide that by his permit approval by the AHJ.

 

I agree you should bid the job, but realize that it can get very ugly.. The engineer will claim you are responsible for the final sizing and calculations... You will claim that the water supply can't meet the requirements.. Where does that leave the project when a new UG must be run to tie into a larger water service?

When this happens, if it happens, I agree with firepe that it should be reported and the engineer should receive a "giving him the business" penalty from the State Board..

I am an AHJ and require the engineer's drawings to have preliminary hydraulic calcs proving out the water supply, and to list data from a valid recent hydrant flow test.

Tennessee goes further and requires the engineer perform full hydraulic calcs sizing the UG service to the building, the system riser, the feed and cross mains, and showing every single head in the building! I would love to see drawings like that everytime. They are very aggressive on enforcing that for this very reason (pump requirements). As I understand, many state projects were going bust because of the pump additions where no pumps were bid, and this prompted the Board of Engineering to put the heat on the HVAC engineers who were doing the sprinkler cartoon drawings like the ones you are bidding..



 
In Ohio, I am told, unless you have a FPE, engineers must have NICET (not sure what level) to lay out sprinklers in the building.

From the one guy in our office who has this - it took him leaving a previous engineeering job and working for a sprinkler contractor at a low pay rate for a period of time before he could get this certification. I think he said he had to have laid out something like 10,000 sprinklers (I could be wrong) and performed the hydraulic calcs before he could take the test to get the certification.

So needless to say, in Ohio, engineers do not lay out the sprinklers.

I would love to be able to do the sprinkler calcs and lay out sprinklers and piping, but while working in Ohio, it is not going to happen.
 
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