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Are tamper switches on backflow OS&Y valves required? 1

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SprinklerDesigner2

Mechanical
Nov 30, 2006
1,251
Of course they are.

But what if the backflow device is dedicated to fire sprinkler but what if the backflow is for both fire and domestic on a large complex such as a shopping mall?
 
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Your question is a little unclear SD2, but I'd say err on the side of caution and bolt em on. Control valve upstream of the sprinkler system...
 
skdesigner,

I sure butchered that, didn't I? I wish this had an edit feature.

Of course if backflows are dedicated to fire only they get tamper switches.

But what if the backflow is used to feed a large facility and serves both fire sprinkler and domestic water needs?
 
Never really seen a setup like that. You would think that there would always need to be a backflow between the sprinkler system and the domestic to prevent backsiphonage into the domestic water.

Are you providing the backflow or is the plumber? Is it a spec'd job? If it were me, I'd let the mech consultant make the call.
 

Technically if the BFP serves both domestic and fire, then it is not part of the NFPA 24 system.. And falls under AWWA or local codes/standards.

From a practical standpipe, if the toilets won't flush, and the ice machine at the $9 smoothie stand doesn't work, then you can bet people are going to be upset and facility maintenance will go investigate and restore the water supply..

Once the fire line splits off from domestic supply, that is NFPA territory and requires supervision.
 
If your building is covered by the IBC then the valves will need to be protected from closure with electronic valve supervision.

Also a partially closed valve may supply domestic needs and never be picked up by complaints of low flow/pressure. But most likely significantly higher fire protection flows would not be met, thus a need for valve supervision.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!


 
Is this outside or in some type of protective enclosure

A good size lock and chain works well for exposed bfp

And especially if they are a good distance from the building alot of wire to run and exposed devices to maintain
 
It's required per IFC Section 903.4. It's not a NFPA 25 or AWWA issue. It's an IFC requirement and the code is very clear on this issue.
 
SD2,
To add to what stookeyfpe said,
903.4 Sprinkler system monitoring and alarms. All valves
controlling the water supply for automatic sprinkler systems, pumps, tanks, water levels and temperatures, critical air pressures,and water-flowswitches on all sprinkler systems shall be electrically supervised.

There are exceptions following this section, however none of them apply in this case. I would have expected the Plumbing Inspector would have had a problem with this arrangement. Also, I hope the designer would have included the plumbing fixures in the hydraulic calcs for the system.
 
"Also, I hope the designer would have included the plumbing fixures in the hydraulic calcs for the system."

Of course I did. It's an Watts RPZ that killed my hydraulics.

Thank you all for your input. Learning something new every day or at least finding firmer footing.
 

Admittedly, I am not the guy for IFC since I have zero experience with it.. But I read the above passage and it doesn't make alot of sense to me in this situation.

Really how far back would this requirement for electrical supervision apply? The situation is a BFP on a potable/fire for a campus, large shopping center, or mall.. So downstream of this BFP you are very likely going to have additional underground valves that aren't electrically supervised but with keyed valve boxes right? Perhaps some would even feed directly to sprinkler risers? And what about the sectional/shutoff valve that supplies the BFP? Does it need to have supervision too? And the valve upstream of it, and upstream of it, etc..? All are also in the "water supply".

It seems to me that particular IFC passage does not apply, since this is upstream of anything that could be considered a "Sprinkler System", which is the title of the section.
 
The requirement for "supervised" alarm components is only applicable to "dedicated" fire protection system components. "Supervised" alarm components are only required for specific occupancies (refer to the IFC for specifics). The valves associated with the combined Backflow Prevention Unit (fire & domestic service) are not part of the "dedicated" fire protection system. Therefore, the tamper switches are not required in this instance.

Remember the standards are minimum.........there are no comments which indicate the tamper switches (or locks) are not allowed IF there is a justified reason/purpose for the increased level of reliability (to make sure the valves remain open at all times).
 
FFP1,
The code section that I quoted was cut and pasted directly from the 2006 IFC and the quote did not include the word "dedicated". Also, this code section does not refer to a specific occupancy type.
 
Even if you win the argument with a local AHJ (code authority), you won't win it with Factory Mutual (or other major property insurors) in my experience.

Any potential to have a privately-owned valve become closed that would impair flow to a building sprinkler system without automatic notification thereof will be nixed.

I gotta go along with stookeyfpe and burnsf on this one.

Good on ya,

Goober Dave
 
byrnesf: You excluded some VERY important words with your post.........."Where supervised automatic sprinkler systems are required by another section of this Code,". {This is the primary point I attempted to address with my quick and short post.}

NFPA 1 (Uniform Fire Code 2006) & NFPA 101 (Life Safety Code 2006) both state the following:

13.3.1.7 Supervision.
13.3.1.7.1* Supervisory Signals. Where supervised automatic sprinkler systems are required by another section of this Code, supervisory attachments shall be installed and monitored for integrity in accordance with NFPA 72, and a distinctive supervisory signal shall be provided to indicate a condition that would impair the satisfactory operation of the sprinkler system. System components and parameters that shall be monitored shall include, but shall not be limited to, control valves, fire pump power supplies and running conditions, water tank levels and temperatures, tank pressure, and air pressure on dry-pipe valves. Supervisory signals shall sound and shall be displayed either at a location within the protected building that is constantly attended by qualified personnel or at an approved, remotely located receiving facility. [NFPA 101:9.7.2.1]

Read Sections 13.3 through 13.3.2.27 of NFPA 1 and/or Sections 11 through 42 of NFPA 101. There are several common occupancies which do not require "supervised" automatic sprinkler systems; therefore, no tamper switches and other monitored electronic devices are required. Some of the common examples would be Mercantile Class B, warehouse storage buildings, existing apartment buildings up to 4 stories (with limitations), as well as lodging & rooming houses among several other occupancies.

NFPA 101 also indicates the following:

4.6.8 Provisions in Excess of Code Requirements. Nothing in this Code shall be construed to prohibit a better type of building construction, an additional means of egress, or an otherwise safer condition than that specified by the minimum requirements of this Code.

Personally, I would prefer that all fire protection system components were electronically supervised; however, the current NFPA documents do not require this level of monitoring/reliability for all occupancies/risks.

I should clarify that my 16 Nov 10 post was unclear/incorrect when I stated "The valves associated with the combined Backflow Prevention Unit (fire & domestic service) are not part of the "dedicated" fire protection system. Therefore, the tamper switches are not required in this instance." I missed the fact that SD2 stated this is a large Mall.......my comments would be correct for a system designed using NFPA 13R or NFPA 13D, but incorrect for any NFPA 13 system which requires "supervised" alarms. A large Mall is considered Mercantile Class A which requires a "supervised" automatic sprinkler system throughout all areas so the tamper switches should be provided for the two valves on the backflow prevention unit (essentially any control valve on the Mall property which would prevent water flow to any of the automatic sprinkler systems in the Mall buildings when fully closed should be electronically supervised!).

I apologize for posting an incorrect statement and for any confusion I caused. We all make mistakes......at least my intentions were good.
 
Pipes and Pumps

It ends at the municipal water supply. If you are upstream of the water supply, l I don't care from the perspective of the BFP or as a AHJ. Downstream, its my responsibility. You install a BFP on a municipal water system with supervised valves, I will consider those valve in my domain because it became a private water supply. SD2 asked and I answered. The BFP involves the sprinkler systems I approve, and they are subject to my approval, along with the plumbing code official.

I know, its a messy business. But at the end of shift, its the municipal H2O supply feeding that unlimited area building.
 
Well that is good to know, thanks for the explanation.

In my past experience the BFP would be in a pit or locked hot box, and the valves for a combined potable/firewater could be locked open, rather than electrically supervised.

Also, since there would not be post indicator valves (PIV)for a business/mercantile type campus, there would be keyed underground valves in curb boxes (completely non-supervised) for the riser lead-ins or other sectional valves in the UG water supply.. So they would also not be electrically supervised, as allowed for by NFPA.

Just curious, would you also require the UG valves in curb boxes to be electrically supervised because they are in your domain? might be hard to maintain the limit switches.
 
No, because valves in a utility box are specifically exempted in the IFC.
 
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