# Basic Cross Connections



## Regulator (Aug 20, 2009)

Who can answer this simple question? Why do we have an air gap at every faucet?


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## Scott K (Oct 12, 2008)

Because the flood level rim of the sink/tub/shower/fixture, etc., if directly connected to the sanitary drainage system, is technically considered an area where raw sewage could be present. The air gap is neccessary to prevent back siphonage (in this case, some potential to occur), and very rarely back pressure.


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## plumbwright (Oct 26, 2009)

we dont have air gaps at every faucet. Most kitchen faucets have pull out sprays, and most peoples tub/showers have hand showers. Is this a trick question?


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## ToUtahNow (Jul 19, 2008)

We have air gaps at all outlets which are over a fixture to prevent a backflow of waste into the potable water system. As for hand sprays at kitchen faucets and showers, they are required to have backflow devices of some type built into them.

Mark


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## SlickRick (Sep 3, 2009)

If it's not a loaded question the answer is to protect against Back-flow/ back-siphonage


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## Regulator (Aug 20, 2009)

Not a loaded question really. I think we all know why we have an air gap where possible. 

But it is acceptable then to bypass the air gap with a hose without having an acceptable backflow preventer installed to control the cross connection created by the hose?


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## Airgap (Dec 18, 2008)

Regulator said:


> Not a loaded question really. I think we all know why we have an air gap where possible.
> 
> But it is acceptable then to bypass the air gap with a hose without having an acceptable backflow preventer installed to control the cross connection created by the hose?


 It's not acceptable to me.:no:


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## SlickRick (Sep 3, 2009)

Regulator said:


> Not a loaded question really. I think we all know why we have an air gap where possible.
> 
> But it is acceptable then to bypass the air gap with a hose without having an acceptable backflow preventer installed to control the cross connection created by the hose?


No way Jose.


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## RealLivePlumber (Jun 22, 2008)

What does your code book say?


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## Regulator (Aug 20, 2009)

RealLivePlumber said:


> What does your code book say?


Good point RealLive,

BC Plumbing Code (2006) 

Sentence 7.6.2.12. *Backflow Preventers*
1) No bypass piping or other device capable of reducing the effectiveness of a _backflow preventer_ shall be installed in a water supply system.

How about the code you follow?


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## Plumber Jim (Jun 19, 2008)

Regulator said:


> Not a loaded question really. I think we all know why we have an air gap where possible.
> 
> But it is acceptable then to bypass the air gap with a hose without having an acceptable backflow preventer installed to control the cross connection created by the hose?


 
have you come across a case recently that someone bypassed a back flow preventer or do you mean like when someone puts a garden hose on a laundry sink faucet without a backflow preventer on it?


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## Regulator (Aug 20, 2009)

Plumber Jim said:


> have you come across a case recently that someone bypassed a back flow preventer or do you mean like when someone puts a garden hose on a laundry sink faucet without a backflow preventer on it?


Jim, the motivation behind this thread has more to do with faucets and hoses. The intent is to allow everyone to voice their opinion on the subject and maybe learn something from the different points of view.

It appears that their may a level of acceptance borne of convenience that is contradiction to code requirements, i.e. diverter valves acting as backflow preventers.

I am simply interested on how plumbers across the continent feel about this.


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## Plumber Jim (Jun 19, 2008)

Well you got me thinking. So i went on the delta website because those are the ones i put in and on the pull out spout faucets they say it has a double check but on the ones with the vegetable prayer ones just says they have a anti siphon device.


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## SlickRick (Sep 3, 2009)

Plumber Jim said:


> Well you got me thinking. So i went on the delta website because those are the ones i put in and on the pull out spout faucets they say it has a double check but on the ones with the vegetable prayer ones just says they have a anti siphon device.


Reg. Has had me thinking too. On the pull outs, If you tried to lay it in the sink would the weight pull it back by its self? Is that there anti syphon device? If not where is it? Is it in the handle?


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## Regulator (Aug 20, 2009)

Plumber Jim said:


> Well you got me thinking. So i went on the delta website because those are the ones i put in and on the pull out spout faucets they say it has a double check but on the ones with the vegetable prayer ones just says they have a anti siphon device.


That can't be right about a double check, dual check maybe. Dual check or anti siphon is it approved? Approved by who? Provisions for this in the code? Maybe this needs a little more thought for the code writers.


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## Regulator (Aug 20, 2009)

slickrick said:


> Reg. Has had me thinking too. On the pull outs, If you tried to lay it in the sink would the weight pull it back by its self? Is that there anti syphon device? If not where is it? Is it in the handle?


Honestly, I'm not sure. But if the hose is spring loaded to the retracted position, I think this is better than a non-approved device.


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## SlickRick (Sep 3, 2009)

Regulator said:


> That can't be right about a double check, dual check maybe. Dual check or anti siphon is it approved? Approved by who? Provisions for this in the code? Maybe this needs a little more thought for the code writers.


I don't understand how a cheesie plastic piece could take the place of a spout that is required to have an airgap... market driven?


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## Regulator (Aug 20, 2009)

slickrick said:


> I don't understand how a cheesie plastic piece could take the place of a spout that is required to have an airgap... market driven?


Could be. Sometimes cross connection control is such a headache things just happen without regulation it seems.


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## Plumber Jim (Jun 19, 2008)

this is the technical specs on a delta pullout spout.

http://www.deltafaucet.com/customer.../980T-SS-DST.html?document=ts&documentIndex=0

What do you think Reg? it says double check. I may have to get to calling my rep and find out more about it.


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## SlickRick (Sep 3, 2009)

Plumber Jim said:


> this is the technical specs on a delta pullout spout.
> 
> http://www.deltafaucet.com/customer.../980T-SS-DST.html?document=ts&documentIndex=0
> 
> What do you think Reg? it says double check. I may have to get to calling my rep and find out more about it.


It does have double check, One on the supply, one on the head. Thats double right?


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## futz (Sep 17, 2009)

Regulator said:


> Honestly, I'm not sure. But if the hose is spring loaded to the retracted position, I think this is better than a non-approved device.
> 
> View attachment 3733


You know how long those pre-rinse springs last in real life, dontcha? Maybe a few months till they sag and the spray sits in the sink.  Kitchen slaves beat the hell out of that stuff.


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## 1703 (Jul 21, 2009)

futz said:


> You know how long those pre-rinse springs last in real life, dontcha? Maybe a few months till they sag and the spray sits in the sink.  Kitchen slaves beat the hell out of that stuff.


That's why we are being told to put dual checks on the riser.


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## service guy (Jun 26, 2008)

Excuse my ignorance, but what exactly is the difference between a "double-check" and a "dual-check?" And what is wrong with a single-check? I am not ccc certified yet.


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## user4 (Jun 12, 2008)

service guy said:


> Excuse my ignorance, but what exactly is the difference between a "double-check" and a "dual-check?" And what is wrong with a single-check? I am not ccc certified yet.


A double check is not testable. a dual check is, and a single check is worthless because they are easily fouled, similar to a vacuum breaker being pretty much worthless as a backflow device even when installed to Chicago code.


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## SlickRick (Sep 3, 2009)

service guy said:


> Excuse my ignorance, but what exactly is the difference between a "double-check" and a "dual-check?" And what is wrong with a single-check? I am not ccc certified yet.


A double check assembly is a testable device to be used in a low health hazard application.

A dual check is a non- testable device that really does not meet back- flow prevention regs. in most states.

A single check does not meet any BF regs. at all.


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## Regulator (Aug 20, 2009)

service guy said:


> Excuse my ignorance, but what exactly is the difference between a "double-check" and a "dual-check?" And what is wrong with a single-check? I am not ccc certified yet.


A double check valve is a testable backflow prevention assembly consisting of two independently acting check valves, inlet and outlet resilient-seated shutoff valves and four properly located resilient-seated test cocks.








*DOUBLE CHECK VALVE ASSEMBLY
*

A dual check valve is a non-testable backflow prevention device consisting of two independently acting check valves.








*DUAL CHECK VALVE*


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## 1703 (Jul 21, 2009)

For you, Regulator:

lawn irrigation RP with a boiler drain screwed in the y strainer


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## Regulator (Aug 20, 2009)

Colgar said:


> For you, Regulator:
> 
> lawn irrigation RP with a boiler drain screwed in the y strainer


ARRRGGHH! You can send 'em to college, but you can't make 'em think.

Good shot Colgar!


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## Airgap (Dec 18, 2008)




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## Airgap (Dec 18, 2008)




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## SlickRick (Sep 3, 2009)

Airgap said:


> View attachment 3861


Is that a HB VB I see there?


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## Tieger plumbing (Nov 13, 2009)

*Tieger plumbing*



plumbwright said:


> we dont have air gaps at every faucet. Most kitchen faucets have pull out sprays, and most peoples tub/showers have hand showers. Is this a trick question?


The hand held showers / kitchen faucets should have a check valve already built in if not another type of back flow preventor


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## TheMaster (Jun 12, 2009)

My grohe ksink faucet does and my handshower has a vaccum breaker at the hose connect on the wall. I feel safer for sure.:thumbup:


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## Regulator (Aug 20, 2009)

slickrick said:


> Is that a HB VB I see there?


It looks like it to me. But where is the hose going? Above the vacuum breaker = backpressure.


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## Regulator (Aug 20, 2009)

TheMaster said:


> My grohe ksink faucet does and my handshower has a vaccum breaker at the hose connect on the wall. I feel safer for sure.:thumbup:


Vacuum breaker on the shower hose :thumbsup:.


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## Tieger plumbing (Nov 13, 2009)

*Tieger plumbing*



Regulator said:


> Who can answer this simple question? Why do we have an air gap at every faucet?


 
Actually the question should be what determines the height of the air gap and what height should an air break be and why

Simple answer to protect the potable water supply to your question in lieu of a vacuum breaker :blink:


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## SlickRick (Sep 3, 2009)

Tieger plumbing said:


> Actually the question should be what determines the height of the air gap and what height should an air break be and why
> 
> Simple answer to protect the potable water supply to your question in lieu of a vacuum breaker :blink:


Reg. stated his question correctly.

Airbreak applies to drainage only.

Airgap applies to both drainage and water distribution.

Airgap is the ultimate protection , it does not rely on mech. parts to function.


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## studmaster1 (Dec 10, 2011)

I think air gaps, especially on mop or service sinks are too easily circumvented by using a hose. The best form of back flow prevention is an RPZ. Any testable device is required to be tested and certified at least annually. Any non testable device (ASSE# 1024 among others) is to be either replaced or rebuilt every 5 years. If you check on the CDC's website you can see we still have a relatively high number of waterborne illnesses reported every year from cross connections. Irrigation companies are the worst, they almost always use the wrong BFP and usually don't tell people why they are important.


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## SlickRick (Sep 3, 2009)

That's why you have vacuum breakers on faucets w/ hose threads.


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## GrumpyPlumber (Jun 12, 2008)

studmaster1 said:


> I think air gaps, especially on mop or service sinks are too easily circumvented by using a hose. The best form of back flow prevention is an RPZ. Any testable device is required to be tested and certified at least annually. Any non testable device (ASSE# 1024 among others) is to be either replaced or rebuilt every 5 years. If you check on the CDC's website you can see we still have a relatively high number of waterborne illnesses reported every year from cross connections. Irrigation companies are the worst, they almost always use the wrong BFP and usually don't tell people why they are important.


I'll bet money that within ten years all new homes will require BF on service mains.


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## stillaround (Mar 11, 2009)

SlickRick said:


> That's why you have vacuum breakers on faucets w/ hose threads.


 They enforce that here..if its a laundry tub fct. with hose threads it must have a vacuum breaker


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## SewerRatz (Apr 25, 2009)

futz said:


> You know how long those pre-rinse springs last in real life, dontcha? Maybe a few months till they sag and the spray sits in the sink.  Kitchen slaves beat the hell out of that stuff.


That is why around here they make us install the pre-rinse hose where it is not long enough to reach in the sink.


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## Tommy plumber (Feb 19, 2010)

studmaster1 said:


> I think air gaps, especially on mop or service sinks are too easily circumvented by using a hose. *The best form of back flow prevention is an* *RPZ.* Any testable device is required to be tested and certified at least annually. Any non testable device (ASSE# 1024 among others) is to be either replaced or rebuilt every 5 years. If you check on the CDC's website you can see we still have a relatively high number of waterborne illnesses reported every year from cross connections. Irrigation companies are the worst, they almost always use the wrong BFP and usually don't tell people why they are important.


 






In reality, the best form of backflow prevention is an airgap. No mechanical parts, only requires a visual inspection to see if it's operating properly and it's the cheapest to maintain. 

And yes, irrigation workers are to blame for circumventing standards with regard to backflow prevention. I will add some plumbers to that list as well. More than one time I've heard a plumber tell a home owner that those pesky little vacuum breakers are not really needed on the hose spigots; they're just a nuisance that has to be there until after the inspection, then we can remove them.


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## deerslayer (Mar 29, 2012)

I did some work for Dow Chemical a few years back when they bought a chemical company we did work at. We removed multiple RPZ's and replaced them with airgap connections for anything that was even remotely considered high hazard. They would go as far as dumping city water in a tank through an airgap and pumping it to the chemical portions as needed in some of the operations. They were very serious about airgaps on everything!


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## TraTech (Jan 22, 2012)

GrumpyPlumber said:


> I'll bet money that within ten years all new homes will require BF on service mains.


It's already happening in Calgary Alberta
All commercial property must have a minimum of a dcva on the water main and they are expanding this to residential which means good money in adding expansion tanks to all HWT in the near future


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## victoryplbaz (May 19, 2012)

GrumpyPlumber said:


> I'll bet money that within ten years all new homes will require BF on service mains.


They tried to already do that in Chandler, Az about 15 years ago. They did whole neighborhood and then the lawsuits flew. I guess the city lost and now they have to maintain them.


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## SlickRick (Sep 3, 2009)

victoryplbaz said:


> They tried to already do that in Chandler, Az about 15 years ago. They did whole neighborhood and then the lawsuits flew. I guess the city lost and now they have to maintain them.


The City of Longview sent me to every training coarse that Texas A&M had to offer, including testing and administrating Cross-connection programs. The State acted like they were getting ready to lower the boom on these cities. It never happened. If I had a question for the TCEQ that was over compliance, their response was that I knew more than they did. I think it was one guy sitting in a cubical in Austin.


They tried it in Longview in the early '90's a year before I took over, and did not address thermal expansion issues, they ended up telling the plumbers to remove them due to liability issues. A residence is considered a low health risk, and if VB's are installed on HB's, anti-siphon ballcocks are installed properly, no risk actually exist. ( not including irrigation systems). Texas has a customer service inspection endorsement to check the cust. side.

Requiring a BFP , and not requiring a TE tank is trading one hazard for another.

That is what we have going on here on rural water systems. They are installing non-testable devices at the meter, and we are continually getting calls on T&P discharging. The purveyors think they are in compliance, but they don't have a clue.

The laws have been on the books since the early '90's and proper enforcement is still not in place.

That has been more than 20 years. I will take the 10 year bet.


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## DesertOkie (Jul 15, 2011)

Some new developments in Tucson are putting them in. They enforce pretty well there as far as businesses. 

Here in Muskogee OK the have meters with them, the water guys end up taking them out because the clog up.


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