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Legionella & Water Heaters-Seattle Times

is never too expensive. The real expense is the loss of life or long term effects if not death.

If codes could catch up with technology then it would be a requirement for these things along with point of use controls to meet the "anti-scalding" issues.

I really need to get over to TACO soon, hey I am right around the corner, just can't seem to find time, in fact I owe John Barba a lunch or something. I know quite a while ago John White invited me I really must go.
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Comments

  • bobbyg_14bobbyg_14 Posts: 3Member


    thanks for sharing. this will be great to help explain the dangers of "open systems".
  • AlexiaAlexia Posts: 10Member


    I have an open system, but wonder if it's ok. Cold water feeds through the copper fin baseboard, through the water heater, then to the faucets. The water is flushed many times a day without any circulator or timer. A check valve between the cold in line and hot feed to the faucets gives priority to domestic hot water, with the house pressure presumably overpowering the little Taco circulator. A simple system that works very well. I hate to think I'm getting us sick with it though.

    My only concern with it to date has been summer condensation caused by the cold water running through the baseboard everytime hot water is used. It has been fine so far but we have been heating.
  • Paul PolletsPaul Pollets Posts: 3,236Member
    Not OK

    This is not OK. I'd recommend separating the heating side from the domestic water system. Since you're using baseboard, you may want to consider a dedicated mod-con boiler and indirect tank, or a combo appliance like the Triangle Tube Delta.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Doug_7Doug_7 Posts: 209Member
    Codes ?

    I know this is a dangerous practice - but is it against the code ?

    I am discussing this situation with the owners of a new 176 suite condo that was built with one water boiler, with one supply header and one return header for both DHW and Building Heating (176 fan-coils).

    Is there any movement to change the codes - anywhere ?

    Thanks.

    Doug
  • Paul PolletsPaul Pollets Posts: 3,236Member
    That depends...

    ...on the local administrative authority. Seattle and King County allow the use of water heaters as a heat source. These systems were installed a a "budget" system, not to represent what could be done with better components. The code is for 'minimum' standards, and in this case, has served the public poorly. Code officials were lobbied to allow less expensive systems to be installed. Lawsuits seem to be the route of code changes these days.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • Josh M.Josh M. Posts: 360Member


    I think it's a matter of time before open systems are banned. The government can't ignore the facts anymore.

    I am sick and tired of bidding against these guys willing to put in Horse Crap!

    I wonder what's going to happen when all of these high rise condo buildings with open radiant systems start causing people to get sick. Maybe then they'll listen.

    BTW, in other good news, I got a bulletin that Rinnai will no longer warranty their water heaters in a closed loop application!
  • Doug_7Doug_7 Posts: 209Member
    Local Codes require flushing dual systems

    I checked the local codes (Alberta), and there was a code addition made in December 2006 to the code for Dual Purpose Combination DHW / Space Heating Systems. The Dec 2006 code addition is:

    2.8 Where the potable water and the heat transfer fluid are not separated, a means shall be provided to prevent stagnation by recycling the system at least once every 24 hrs.

    The code does not explain this clause or show this feature on any of the diagrams, but it is pretty clear what it means.

    The 176 suite condo has a timer in each suite that opens the hot water flow through the suite's fan-coil for 90 seconds every 24 hours. There is no way for owners to disable this feature without getting into the wiring - but they do complain about it, because the fan comes ON and blows hot air.

    The installer explained that this feature was to combat air locks.

    So I guess this meets code.

    Doug
  • J.C.A._3J.C.A._3 Posts: 2,981Member
    So..it meets code.

    I will respectfully ask Mr. Etherton for an opinion, and I'm sure it will be a doozy!!!

    I will also ask Mr. Yates for a rebuttal. I'm thinking you might get the same answer...and a whole lot of left out "swear words".

    If you refuse to do this work, you lose a job. If you DO this work...you risk your company and the livelihood of your entire team.Why take the chance?

    We're better than this. Always have been...always will be.

    If we are asked to commit this foolishness,refuse and move on.

    Codes or not....we all know this is a lawsuit waiting to happen. Why even give it a shot? Chris
  • Doug_7Doug_7 Posts: 209Member
    Adequate protection ?

    Not saying I agree. Just saying I checked the code and this condo does appears to meet the local code. In fact the local code was specifically changed to allow this.

    So the question is - Does this code provide adequate protection ?

    Doug
  • Alexia_2Alexia_2 Posts: 1Member


    Is legionella still a concern if inlet water is forced through the heating loop whenever hot water is used? I wasn't sure if you were refering to legionella or another problem, Paul. The open loop in my house seems to equate to little more than a longer pipe running to my water heater. There just isn't any stagnant area. Well, there is about 12" between where the cold feed goes in and the hot supply goes out. It has the check valve in the middle. I'm sure it must get some summer time circulation from turbulance, though.
  • In a word

    NO
  • In another single word

    YES
  • Damned if I can understand

    that anyone still has a single doubt that open systems, by their very nature, are a super-amplifier. The evidence is far too compelling and overwhelming to believe otherwise - unless, of course, the doubters just happen to be in a position to profit from the sales of open systems, be they installers or purveyors.

    Codes be damned. The self-contradictions within the codes are an embarrasment and it is blatantly obvious the codes are goverened by slick lobbyists and lawyers. Long gone is the common sense that fostered the original intent - to protect the health of the nation. Today's codes pander, instead, to those who stand to profit from the changes and alterations that have dilluted their original scope and purpose.

    Mark Eatherton and I jointly submitted a proposal to have open systems banned from our national codes - for all the obvious reasons. I doubt I need tell you, but it was rejected outright - a 100% vote against any change.
  • J.C.A._3J.C.A._3 Posts: 2,981Member
    Notice....

    That he left out "swear words"?

    Mr.Yates has more to add...but didn't...on the YES and the NO answer .

    I'm still waiting to hear what M.E. has to say...being a survivor..and all. JCA .

  • Alexia_3Alexia_3 Posts: 1Member


    The whole subject is confusing. I've been Googling only to find conflicting info. Many links say chlorine doesn't kill legionella, mostly discussing the treatment of cooling tower water. Then there are many other link detailing studies showing free chlorine doeas kill legionella, but it takes minutes to do it - longer than many/some other bacteria.

    I've worked in many apartment communities with literally hundreds of feet of interior water lines at room temp and domestic hot water circ systems of the same lengths with ~120 degree water. If chlorine doesn't kill it, if it thrives at room temps, if it thrives at "typical" heated temps, it seems there would be a lot of dead people in my field. But there isn't? I'm at a loss.
  • Doug_7Doug_7 Posts: 209Member
    Any Reason ?

    Did the code officials give a reason for not accepting your proposal to have open systems banned ?

    Normally a decision such as this would equire discussion and analysis.

    What reason did they give ?

    Doug
  • Reasons given....

    BEGIN ICC comment;

    P48-07/08

    PART I – IPC

    Committee Action: Disapproved

    Committee Reason: The proposed requirements appear to be overly restrictive and would limit the application
    of these types of water heating units.

    Assembly Action: None



    PART II – IRC-P

    Committee Action: Disapproved

    Committee Reason: Some of the language is ambiguous and no rationale was provided for the maximum
    developed length of the potable water circuit.

    Assembly Action: None

    Not much to go on but the committee’s didn't have much to says since there wasn’t much (if any?) live testimony on the proposals.



    The next step in the process (if you wish to continue forth) is to submit a public comment for each of these proposals. Public Comment forms are on our website at



    http://www.iccsafe.org/cs/codes/2007-08cycle/07-08_Public_Comment_Form.doc



    Fax or email in by June 9.

    END OF ICC statement, begin Mark Eatherton comment;

    To All, We still have a decent shot at getting this in the books, but it is going to require a concerted effort, and a little time in filling out the online form. It is too late to use my paper podium (monthly article in Contractor Magazine) so I am going to have to depend on the faster media (internet) and people like yourselves in hopes that we can convince these officials of the error of their ways.

    The committee that voted on this consists of 15 people with varying backgrounds. I don't envy them for the task they had to carry out, and had Dave or I been able to attend the hearings, I assure you the outcome would have been completely different. Such is the nature of the beast.

    If you have a suggestion of some other plumbing related web sites that you think mught be interested in helping to reverse this wrong doing, please post it here and I will go visit the site and make posts.

    Thank you for your interest, and thank you in advance for your help in righting the wrong.

    ME
  • Doug_7Doug_7 Posts: 209Member
    Managing Risk - Legionella

    Alexia - You are getting a good understanding of the issues.

    In terms of what kills Legionella and other bacteria I would worry less about chlorine and rely more on time-temperature to kill bacteria. Most of the chlorine is gone when the water reaches your house, having been used up in the distribution sysyem. The Seattle Times article says 140 degrees for 32 minutes or 151 degrees for 2 minutes.

    What really grows lots of Legionella is a large volume of stagnant warm water, such as a stagnant water heater tank held at too low a temperature for a long period of time. Shower in that water and inhale some shower water and you have a high risk of infection.

    Smaller quantities of warm water that may be present in stagnant hot domestic water piping can also present a risk - but obviously a much lower risk because it is in a small pipe not in a big tank, we are dealing with a much smaller volume and it flushes out fairly easily.

    Stagnant hot water lines should be avoided, but it is not always possible to eliminate them - e.g. if someone is away for a period of time their water lines are stagnent. Vacation homes are a problem.

    It is good practice to flush out stagnant hot or cold domestic water lines before first use. In Ontario they even passed a law requiring all schools to flush out all drinking water lines and fountains for 5 minutes before school every morning. That was for lead, but the principle is the same.

    The other critical risk factor is how long a period of TIME the line is stagnant. If the line is not stagnant very long or is flushed frequently, the risk is much lower.

    In toxicology the underlying principle is "The dose makes the poison". It takes a certain quantity of bacteria to create a health risk. There are some bacteria in the incoming water, but that is not a risk. When they are allowed to multiply greatly, that increases the risk.

    The risk depends on the concentration of bacteria in the water. The risk may be high, medium or low depending on how long the bactriia have been allowed to grow, and whether that was in a tank or pipe.

    Ordinary domestic hot water tanks present a risk if the time-temperature is not managed to kill bacteria rather than grow them. We keep out domestic hot water tank at 140 degrees and mix it down to about 130 degrees for users.

    There is no such thing as zero risk and no such thing as 100% risk. You need to understand the variables to minimize the risk.

    You will get lots of opinions on this one. Keep checking your sources and deal in facts and you will figure it all out.

    Doug

    p.s. I don't drink out of the hot water tap.

  • As a near death survivor of L.D.

    I think I can tell you that you DON'T want to get this disease. As for potable water, copper water lines are a natural suppressant to bacterial growth. That is why they use copper sulfate crystals to kill off bacerialogical growths in open ponds. The bacterium still survives in copper pipes, just not in higher quanities.

    It is the use of plastic tubing that causes a breeding ground/bacterial amplifier. The bacteria is omnipresent. It's in the dirt, and subsequently the water. Legionairres disease is THE most misdiagnosed disease IN THE WORLD, according to the Center for Disease Control and Prevention (CDC).

    It shows itself in the form of bacterial lung infections. It attacks people with depressed immune systems.

    It is here, and it is killing people on a daily basis, it's just hiding behind the mask of bacterial lung infections. I am personally aware of 2 cases of people who contracted LD from their combination open loop space/DHW system. Both were installed by the same company, who continues to install them, because they can, because under the current provisions of the code, they are approved.

    Stop trying to convince yourself that it is OK. The sooner you get rid of it, the sooner you alleviate yourself of the possibility of getting a good dose of LD.

    The funny thing about ALL of this is that Dave and I have absolutely NOTHING to gain from seeing this change passed. Nothing other than upholding the credo by which we live, which is "Protecting the health of the nation". The credo of the plumber.

    I saw one article during my research where the CDC did a random blood test looking for the antigens associated with LD, and they found that 90% of the people they tested had been exposed to this deadly disease. If you think you won't catch it, I wish you the best of luck. If you do catch it, seek treatment immediately, and your chances for survival are good.

    Why take chances?

    ME
  • What was submitted to the IPC...

    PUBLIC CODE CHANGE PROPOSAL FORM
    FOR PUBLIC PROPOSALS IN THE INTERNATIONAL CODES

    2007/2008 CODE DEVELOPMENT CYCLE
    CLOSING DATE: All Proposals Must Be Received by August 20, 2007
    The 2007/2008 Code Development Hearings are tentatively scheduled for
    February 18 – March 2, 2008, location TBD.

    1) Name: Mark Eatherton Date: July 17, 2007
    Jurisdiction/Company: Self
    Submitted on Behalf of: Self
    Address: 1832 S. Utica Street
    City: Denver State: Colorado Zip Code: 80219
    Phone: 303-936-7606 E-mail address:[email protected]

    2) Copyright Release: In accordance with Council Policy #28 Code Development, all Code Change Proposals, Floor Modifications and Public Comments are required to include a copyright release. A copy of the copyright release form is included at the end of this form. Please follow the directions on the form. This form as well as an alternative release form can also be downloaded from the ICC website at www.iccsafe.org. If you have previously executed the copyright release, please check the box below:
    X 2007/2008 Cycle copyright release on file

    3) Indicate appropriate International Code(s) associated with this Public Proposal – Please use Acronym 2006 IPC
    If you have also submitted a separate coordination change to another I-Code, please indicate the code: 2006 IRC and 2006 IMC
    (See section below for list of names and acronyms for the International Codes).

    4) Be sure to format your proposal and include all information as indicated on Page 2 of this form.

    5) Proposals should be sent to the following offices via regular mail or email. An e-mail submittal is preferred, including an electronic version, in either Wordperfect or Word. The only formatting that is needed is BOLDING, STRIKEOUT AND UNDERLINING. Please do not provide additional formatting such as tabs, columns, etc., as this will be done by ICC. REMOVE TRACKING CHANGES, AUTOMATIC NUMBERING, OR ANY OTHER ADVANCED FORMATTING TOOLS THAT ARE PROVIDED BY WORD, FROM FILES CONTAINING YOUR CODE CHANGE PROPOSAL THAT YOU SEND TO ICC.

    Please use a separate form for each proposal submitted. Note: All code changes received will receive an acknowledgment.
    Please check here if separate graphic file provided. X Identified as graphic PWHXFP.JPG
    Graphic materials (Graphs, maps, drawings, charts, photographs, etc.) must be submitted as separate electronic files in .CDR,.IA,.TIF or .JPG format (300 DPI Minimum resolution; 600 DPI or more preferred) even though they may also be embedded in your Word or Wordperfect submittal.

    Code Send to:
    IBC - International Building Code
    IEBC - International Existing Building Code
    IFC - International Fire Code
    IFGC - International Fuel Gas Code
    IPC - International Plumbing Code
    IPSDC - International Private Sewage Disposal Code
    IPMC - International Property Maintenance Code
    IWUIC - International Wildland-Urban Interface Code
    IZC - International Zoning Code
    ELECT - International Code Council Electrical Code– Administrative Provisions
    __________________________________________________________________

    IECC - International Energy Conservation Code
    ICC PC - ICC Performance Code
    IMC - International Mechanical Code
    IRC - International Residential Code

    International Code Council
    Chicago District Office
    Attn: Diane Schoonover
    4051 West Flossmoor Road
    Country Club Hills, IL 60478-5795
    Fax: 708/799-0320
    [email protected]



    ____________________________________________

    International Code Council
    Birmingham District Office
    Attn: Annette Sundberg
    900 Montclair Road
    Birmingham, AL 35213-1206
    Fax: 205/592-7001
    [email protected]





    CODE CHANGE PROPOSAL
    Please provide all of the following items in your code change proposal. Your proposal may be entered on the following form, or you may attach a separate file. However, please read the instructions provided for each part of the code change proposal. The sections identified in parentheses are the applicable sections from CP #28 Code Development. The full procedures can be downloaded from www.iccsafe.org.
    Code Sections/Tables/Figures Proposed for Revision (3.3.2):
    501.2 Water heaters as space heater.
    608.1 General
    Note: If the proposal is for a new section, indicate (new).
    Name/Company/Representing (3.3.1):
    Mark Eatherton, representing myself.
    Note: You must indicate your name and the full name of who you are representing. Do not use acronyms.
    Proposal: NOTE: PLEASE READ ITEM 5) of the first page of this form for formatting instructions.





    Note: Show the proposal using strikeout, underline format. At the beginning of each section, one of the following instruction lines are also needed:
    •Revise as follows
    •Add new text as follows
    •Delete and substitute as follows
    •Delete without substitution
    Note: The only formatting that is needed is BOLDING, STRIKEOUT AND UNDERLINING. Please do not provide additional formatting such as tabs, columns etc. as this will be done by ICC. DO NOT USE THE TRACKING CHANGES OPTION, AUTOMATIC NUMBERING, OR ANY OTHER ADVANCED FORMATTING TOOLS PROVIDED BY WORD.

    Begin modifications to section 501.2

    •Add new text as follows (indicated by underlined bold text)


    Where a combination potable water heating and space heating system requires water for space heating at temperatures higher than 140 ° F (60 °C) a master thermostatic mixing valve complying with ASSE 1017 shall be provided to limit the water supplied to the potable hot water distribution system to a temperature of 140 ° F (60 °C) or less. The use of an isolation heat exchanger to separate the potable hot water from the space heating fluid is required in order to avoid contaminating the potable hot water heating system due to stagnant water conditions and bacterial amplification typically found within dormant space heating systems. If the fluid within the space heating systems will contain potentially harmful chemicals, the heat exchanger shall be required to be double walled as dictated by other sections of the International code, and the make up water connection shall comply to provisions of section 608.1 of the 2006 IPC. Additionally, the introduction of potable cold water into the water heater/space heating heat exchanger combination shall be routed such as to purge the heat exchanger heat source circuit with each and every draw of potable hot water to avoid possible stagnation and potential bacterial amplification. (See attached graphic PWHXFP.JPG)

    End of modifications to section 501.2

    Begin modifications to section 608.1

    •Add new text as follows (indicated by underlined bold text)

    608.1 General. A potable water supply system shall be designed, installed and maintained in such a manner so as to prevent contamination from non potable liquids, solids or gases being introduced into the potable water supply through cross-connections or any other piping connections to the system This includes the use and or application of combination direct space heating/domestic water systems. The use of combination direct space heating/potable domestic hot water heating systems shall not be allowed unless the space heating water is isolated from the potable water heating system through the use of a properly sized heat exchanger to isolate the two fluids. The installation shall comply to the provisions of section 501.2 of the IPC and all other sections of the International codes pertaining to maintaining the potability of the water distribution system. Backflow preventer applications shall conform to table 608.1, except as specifically stated in Sections 608.2 through 608.16.9 The space heating portion of the combination system shall comply with all other code provisions pertaining to closed loop space heating systems as provided in the international Mechanical Code and the International Residential Code, as it pertains to the required use of isolation valves, expansion tanks and air elimination systems.

    End of modifications to section 608.1

    Supporting Information (3.3.4 & 3.4):



    Note: The following items are required to be included:
    1. The proponent shall clearly state the purpose of the proposed code change (e.g., clarify the Code; revise outdated material; substitute new or revised material for current provision of the Code; add new requirements to the Code; delete current requirements, etc.)

    As currently allowed under the ICC codes, the combination “open and direct” potable water and space heating systems can and do allow the potable water laying in the in-floor radiant floor distribution system, as well as other methods of space heating systems to become stagnant when not used for long durations of time. This contaminated water is then charged into the domestic hot water heating systems when the domestic hot water heating system is eventually used again and the occupants are then exposed to elevated aerial bacterial contamination including Legionella Pneumophila (Legionairres Disease hereafter referred to as LD), Pontiac Fever and a host of other water born diseases that can and do flourish and multiply under these conditions. This LD bacteria is typically aerosolized via shower heads and lavatory faucet aerators, and inhaled deep into the lungs, causing bacterial pneumonia in people with depressed immune systems. Having contracted and fortunately survived exposure to LD, I can tell you from personal experience that the near death conditions I suffered through are a situation that no person should ever be exposed to. The Center for Disease control has stated publicly that cases of LD are one of the most under reported illness in the world. It is a known fact that the disease is a water borne disease and the bacteria responsible for causing LD is omni present and will flourish and amplify under the ideal conditions found within these open/direct space heating systems during extended periods of non use. I am personally aware of three cases where combination systems have created confirmed cases of occupants contracting LD, and at least two cases where litigation is or was considered due to the exposure to this deadly disease.

    2. The proponent shall justify changing the current code provisions, stating why the proposal is superior to the current provisions of the Code. Proposals that add or delete requirements shall be supported by a logical explanation which clearly shows why the current Code provisions are inadequate or overly restrictive, specifies the shortcomings of the current Code provisions and explains how such proposals will improve the Code. By eliminating the use of open and direct potable water combination heating systems, the possibility of exposure and contraction of these deadly water borne diseases is significantly eliminated.
    3. The proponent shall substantiate the proposed code change based on technical information and substantiation. Substantiation provided which is reviewed in accordance with Section 4.2 and determined as not germane to the technical issues addressed in the proposed code change shall be identified as such. The proponent shall be notified that the proposal is considered an incomplete proposal in accordance with Section 4.3, and the proposal shall be held until the deficiencies are corrected. The proponent shall have the right to appeal this action in accordance with the policy of the ICC Board. The burden of providing substantiating material lies with the proponent of the code change proposal. A minimum of two copies of all substantiating information shall be submitted. (3.4)

    It is entirely plausible that during summer vacations whereby the family completely vacates their home for an extended period of time for a trip cross country, or a home is un-occupied for an extended period of time (i.e. house empty, for sale) that the water laying within the in floor radiant distribution system can become stagnant and actually harbor and amplify substantial bacterial colonies, as indicated by the Center for Disease Control.. While the family is gone, or the home unoccupied for extended periods of time, the water borne bacteria have ample time and ultimately perfect conditions under which it can grow, multiply and increase its quantity and strength. When the family returns from vacation, or the home is re-occupied, and occupants start using the potable hot water, they are being exposed to extremely elevated counts of water borne bacteria in quantities that the original code approval committee could have never conceived possible.

    4. The proponent shall submit a bibliography of any substantiating material submitted with the code change proposal. The bibliography shall be published with the code change and the proponent shall make the substantiating materials available for review at the appropriate ICC office and during the public hearing.

    On line links to web sites detailing the culturing of and amplification of Legionella Pneumophilla and other water borne diseases in potable water systems are as follows;
    http://www.cdc.gov/ncidod/dbmd/diseaseinfo/legionellosis_g.htmwww.legionella.org/100960699-1.pdf
    http://www.estechlab.com/legionella.htm
    http://www.contractormag.com/articles/column.cfm?columnid=98
    http://www.contractormag.com/articles/column.cfm?columnid=17
    http://www.contractormag.com/articles/column.cfm?columnid=162
    http://www.contractormag.com/articles/column.cfm?columnid=656
    http://www.contractormag.com/articles/column.cfm?columnid=645
    http://www.contractormag.com/articles/column.cfm?columnid=668
    http://www.contractormag.com/articles/column.cfm?columnid=681
    www.scirus.com/srsapp/search?q=legionella&t=all&ds=bls&ds=ide&ds=mps&ds=cps&ds=sd&ds=nsc&q=%22community+acquired+pneumonia%22&t=all&g=r

    Referenced Standards (3.4 & 3.6):

    List any new referenced standards that are proposed to be referenced in the code and provide a minimum of two copies. For ICC rules on referenced standards, see Section 3.6 of CP #28. No new standards are proposed, just elimination of all references to allowing potable open direct combination space and domestic hot water heating systems without the protection afforded by heat exchangers.

    Cost Impact (3.3.4.6):

    Note: The proponent shall indicate one of the following regarding the cost impact of the code change proposal:
    1) The code change proposal will increase the cost of construction, but will eliminate potential litigation costs associated with the contraction of LD, potential loss of life, and possibilities of permanent disability due to current code allowances as it pertains to the use of “open and direct” potable water heating/space heating systems;
    This information will be included in the published code change proposal.


    COPYRIGHT RELEASE FOR
    2007/2008 PROPOSALS, MODIFICATIONS and PUBLIC COMMENTS SUBMITTED ON
    ICC CODES
    PRODUCED & PUBLISHED BY THE
    (March 28, 2007)
    INTERNATIONAL CODE COUNCIL

    This form is required for all Proposals, Floor Modifications and Public Comments submitted to the International Code Council. Only one signed Copyright release form is required for the entire 2007/2008 Cycle and will be kept on file and can be used for all Proposal, Floor Modification and Public Comment submittals you submit to ICC unless you represent multiple entities. An executed form is required for each entity represented.

    I hereby grant and assign to ICC all rights in copyright I may have in any authorship contributions I make to ICC in the 2007/2008 Cycle in connection with any proposal and public comment, in its original form submitted or revised form, including written and verbal modifications submitted in accordance with Section 5.5.2 of CP #28. I understand that I will have no rights in any ICC publications that use such contributions in the form submitted by me or another similar form and certify that such contributions are not protected by the copyright of any other person or entity.

    Signature:

    Please type or print full name: Mark Eatherton, licensed master plumber.

    Jurisdiction/Company:___Representing myself_____________________

    Entity Represented: Representing myself ________________________________________________________

    Contact info: Phone: 303-DELETED____________ Email:[email protected]

    Date signed: __July 17h, 2007_____

    PLEASE FAX OR MAIL THE SIGNED COPYRIGHT RELEASE TO:

    Fax: 708-799-0320 Mail: ICC Codes & Standards Development
    Chicago District Office
    4051 W. Flossmoor Road
    Country Club Hills, IL 60478-5795

    END ICC statement, begin Mark Eatherton comment: The attached JPEG is what we proposed to the committee.

    ME
  • What YOU can do about it....

    Begin ICC Public comment form;

    ICC CODES - PUBLIC COMMENT FORM
    FOR PUBLIC COMMENTS ON THE g2008 REPORT
    OF THE PUBLIC HEARINGSh

    PLEASE SEE BACK OF FORM FOR PROCEDURES ON SUBMITTING PUBLIC COMMENTS. ALL SUBMITTALS MUST
    COMPLY WITH THESE PROCEDURES.

    CLOSING DATE: All Comments Must Be Received by June 9, 2008. The 2008 Final Action Hearings will be held September 17-23, 2008 in Minneapolis, Minnesota


    1) Please type or print clearly: Public comments will be returned if they contain unreadable information.

    Name: Date:
    Jurisdiction/Company:
    Submitted on Behalf of:
    Address:
    City: State: Zip +4:
    Phone: Ext: Fax:
    e-mail:

    2) Copyright Release: In accordance with Council Policy #28 Code Development, all Code Change Proposals, Floor Modifications and Public Comments are required to include a copyright release. A copy of the copyright release form is included at the end of this form. Please follow the directions on the form. This form as well as an alternative release form can also be downloaded from the ICC website at www.iccsafe.org. If you have previously executed the copyright release, please check the box below:
      2007/2008 Cycle copyright release on file

    3) Code Change Proposal Number:
    Indicate the Code Change Proposal Number that is being addressed by this Public Comment: ___________________________

    4) Public Comment: The Final Action requested on this Code Change Proposal is: (Check Box)

    Approved as Submitted (AS): Approved as Modified by this Public Comment (AMPC): Approved as Modified by the Code Committee as Published in the ROH (AM): Approved as Modified by Assembly Floor Action as Published in the ROH (AMF): Disapproved (D):


    5) Proposed Modification (AMPC only):






    Modification Continued (Attach additional sheets as necessary)

    6) Reason (State the reason and justification to support the Public Comment. Include a bibliography of any substantiating material. It is the responsibility of the commenter to make the material available at the Final Action Hearing):







    Reason Continued (Attach additional sheets as necessary)


    PLEASE USE SEPARATE FORM FOR EACH PUBLIC COMMENT
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    END ICC Public Comment form, begin Mark Eatherton comment.

    Wallies, as you can see this is a daunting task.Dave and I wnet through numerous iterations before what we submitted as change was finally accepted. I am goin gto take the time to fill out the Public Comment Form myself, and will save down a copy of the actual Word document. If you want to receive a copy of my completed form, which will save you LOTS of time, send me an email and I will bounce it back to you. you will have to take the initiative to complete the release form and fax it back to the folks at the ICC, otherwise, it goes to the round file.

    My email address is [email protected]

    You DON'T have to be a licensed plumber to comment. In fact, it might make even more of an impression if they get comments from all walks of life.

    Every little bit helps. Thanks for your assistance in this critical matter.

    Mark Eatherton
  • Doug_7Doug_7 Posts: 209Member
    Codes ?

  • Doug_7Doug_7 Posts: 209Member
    Risk of Legionella

    Mark - No one doubts your knowledge or passion. I am not trying to convince myself of anything and I have nothing to gain or lose either.

    My background is in science. I managed Medical, Health and Toxicology departments. I have done numerous risk assessments. I am suggesting we need to try to quantify the relative RISK. The bacteria is everywhere and we are all exposed to it. When does that exposure become a health risk ?

    Risks are not all or nothing. Conventional domestic hot water heating systems pose a serious health risk as you well found out. Open combo heating systems pose another risk. What is that risk ? What is the risk if they are flushed ? Does maintaining the DHW tank at 140 degrees make the risk acceptable. How do you manage the risk ?

    Why did the code authorities not agree with you and Dave ? Did they give you a reason ?

    We are not having an arguement - we are having an agreement. We just need to explain the risks involved better, and try to quantify the risk we are talking about.

    Trying to get Alexia some facts and answers to her questions.

    Doug
  • Doug...

    The comment about trying to convince yourself was not directed at you. It was directed at Alexia.

    I was typing my post when you posted yours, and I could not tell where it would land in the thread. Such is the nature of the beast.

    As for flushing, it will not work as advertised. If a family goes on vacation during the summer months, the heating system will sit stagnant with all the right conditions for bacterial amplification. When the family returns home and starts running the hot water heater, the bacteria are flushed into the DHW tank, which is probably running cooler under a load, it then comes out of the shower head, and is inhaled by a person who's immune system is compromised due to exposure in the airplane to people who are loaded with other bacteria, and BINGO, a normally healthy person is infected.

    I appreciate your comment here and would be more than glad to have you speak out againts this currently allowed practice if youy are interested.

    I think we're both looking and playing off of the same page. If the exposure risk were negligible, we wouldn't be having this conversation. The Europeans reaize the reality o fhte situation and have a "Sanitization" setting on thier water heaters to erradicate the bacteria.

    The problem actualy runs a lot deeper than combination systems. There is a need to develop a whole set of standards as it pertains to DHW heating and distribution systems as well. One step at a time. The code cycle changes every two years...

    As for the code committee, there were two people that I feel were qualified to sit on the committee as polumbers, and they both voted for the change. The others are builders, engineeers, fire protection typoes and of course the rep for the HBA who won't vote for ANYTHING that raises the cost of construction.

    I manage the risk by not giving the bacteria a lot of places to amplify, i.e. open combination direct heating systems. I keep the storage tank at 140 degrees F, and mix down to distribution. I design the circulation return to allow for as thorough heating of the returns as is possible, and I don't use plastic tubing in the distribution system.

    THis part of the job will be getting real easy here real soon. Wilo will be introducing their 1 watt pump in the near future. It is made of brass and is compatible with potable water. Each branch off the main can then be maintained for bacterial growth using scald sanitization along with anti scald protection for the consumer.

    We have a major uphill battle on our hands. THe water heater manufacturers and utility companies are telling the consumers to TURN IT DOWN...and here we are, in the midst of an energy crisis telling them to TURN IT UP!! THeirs is for scald elimination, ours is for protection of the health of the nation.

    But it is a battle worth fighting for.

    Sorry for the confusion.

    Tis also the nature of the beast.

    ME
  • AlexiaAlexia Posts: 10Member


    It may be a case of the same thing by a different name, but I'm not trying to convince myself the system is ok, I'm trying to understand how the system isn't ok. This subject is new to me as previously legionella is something I only associated with A/C. I appreciate very much all of the input here.

    The setup in my home seems to differ from a separated in two ways:

    1. There is about 150 more feet of copper the water must traverse before it reaches my storage tank water heater. The only way the loop can be short circuited and allowed to become stagnant is if the check valve fails - which would be immediately apparant by a loss of hot water. The extra length is more than matched in large homes and buildings, and by homes that are recessed hundreds of feet from the road.

    2. In winter that extra 150 feet also has heated water circulated through it in heating demand cycles. There is no issue of mixing potable and unpotable water as it's all potable water.

    Setup of a heat exchanger would seem to be one and the same, but in a smaller loop, having the same need to prevent stagnation. Is there anything I'm missing? My only "motive" is cost. It costs a lot to do a heat exchanger and second circ pump. It costs a lot more to install a boiler and money is something I'm short on.

    I'm very glad you mentioned the concern with PEX. I was looking at replacing the long 3/4" run to my kitchen sink with 3/8" PEX. It takes forever to get hot water as it is, but I think I'll be looking into copper instead, or just leaving it as it is.
  • Doug_7Doug_7 Posts: 209Member
    Changing the Codes

    I have gone to code meetings and have seen how these decisions are made. It is all about developing codes that ensure the lowest cost for the builders. Unqualified people making self-serving decisions with no accountability. The result is we have some pretty dumb codes, that do NOT keep up with the times.

    The only way to get action from the Code officials is to first get the support of the top regional Public Health oficials. This is a Public Health issue. Public Health oficials speak your language and have a different mandate than low cost construction. They understand health risk.

    If the chief Public Health officer were to write a letter to the Code Officials, expressing the potential health concern and asking the Code officials for a proper Health Risk Assessment on combo heating and DHW systems before they approve them, the fur would really start to fly.

    The Code Officials would then actually have to consult a Doctor - not just listen to the builders with a vested interest.

    This is what it will take to change the codes for combo systems.

    Otherwise it is like batting your head against the wall.

    Doug
  • DarrellDarrell Posts: 303Member
    Curious

    How do the popular DHW recirculation packages that are a crossover at the farthest faucet set from the water heater pushing warm water back into the DCW line factor into this problem? Seems like they woould be charging the DCW, (drinking water), with potentially bateria laden luke warm water.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • ChapChap Posts: 42Member
    google this

    Legionella The Coming of the Third Plague

    Pay close attention to the tests that were done with regard to bacterial amplification. Bear in mind that those tests were done in a time-era when water heater thermostats were factory pre-set to 140F.

    Someone riddle me this: with all that is know about bacterial amplification and LD (A/C cooling towers get their make-up water from where???) and that water heaters are already on the list of known amplifiers, why would anyone connect a perfect breeding ground to an already known problem & thereby amplify the problem? Why is it that given the scientific evidence that's well established and well known, the responsibility to dis-prove the associated dangers should fall on the shoulders of those who meerly pointed out the issues? Why not suggest the purveyors need to prove that what they're doing with potable water cannot or will not degrade the potability?

    Bring forth the hard scientific evidence that proves open systems get a free pass from bacterial amplification issues, that they have no affect upon potability and you'll have my undying, and vocal, support. After years of searching, the only 'evidence' I've been able to locate to support open systems came from those who stand to profit from sales and not a single one ever could produce any real evidence.

    If any product that's not an integral component of a plumbing system degrades the potability of the water, it has no business being incorporated into the system.
  • AlexiaAlexia Posts: 10Member


    I see the incidence of legionella is also strongly related to electric storage water heaters where fuel fired, bottom heated tanks fare significantly better.

    I wonder if gas fired tankless units are pretty much immune as long as they get frequent use? The copper heat exchanger surface must get pretty hot even with a lower temp setting. The combination of frequent 100% flushing, low interum storage volume, copper surface, and high surface temp would seem to all work together.
  • me too

    I've thought about that issue too. But, they are not copper - they are glass-lined steel and even at that, the glass lining terminology is a bit misleading. The anode rod protects the tank's imperfections where the all-to-thin glass lining has pin-holes. Absent the anode rod, the tank's demise is assured.

    Cooking the sediment and cooler layer along the base of gas or oil fired tanks no doubt does have some beneficial bacterial kill rate. How much is unknown and given the newer lowered stat settings since that paper was written, I wonder what affect that had too.

    However, the two deaths in the Pittsburgh area the author traced back to the victim's home's water heaters were both gas-fired.

    So I guess you must decide if there is sufficient evidence to cast a pall over the notion that open systems are ok. Do you simply ban all electric types and give gas/oil fired tanks a blessing? If so, where do indirect tanks fall? And then you need to decide if this is a problem strictly isolated to the tanks. If you believe that to be the case, you'll need to somehow justify the proof-positive from contamination of distribution piping and distal sites. It's more than just the water heater and can be divided into four distinct sections as follows: entry source (well or municipal); point of source for the heated water (the tank); Distribution Network of Piping; and all Points of Use (Distal Sites).

    When I look at the four basic factors that give bacteria a welcome-home greeting: temps between 85 and 133F; biofilms, rust & sediment for food & shelter; pH between 5.0 & 8.5; and stagnation that permits free-roaming bacteria to hang around in one location, I see open systems as an "if you build it they will come" deal. Common sense alone dictates open systems will be a perfect breeding ground.

    It's ultimately your call & decision. My concerns are not yours, obviously, so you're on your own. It's America & the Land of the Free. You've been given enough leads to study the issues and develop your own conclusions. Smoke em if you got em!
  • Alexia...

    The cost of converting your system over to a true isolated closed loop system is probably less than $1,000.00

    THe cost of contracting LD may cost you your life, or worse, pout you seriously out of commision for a long period of time, causing you great financial loss.

    I guess you have to ask yourself, is it worth the risk?

    You've been told all of the facts. THe decision is now in your hands. Do you roll the dice of life, or fix it and sleep well at night knowing you've eliminated one more potential hazard in your and your family's life.

    It's your shot.


    ME
  • AlexiaAlexia Posts: 10Member


    Well, I'm pretty far removed from knowledgable, but the reading is helping. As an open system goes mine appears a little tame. It's really an oversized version of the indirect system you advicate in the letter. If you replace the water-to-water heat exchanger in your's with the fin tube in mine, add a hundred+ feet of copper tube, the piping, flow, pump, and check valve is identical. It lacks the stagnation and PEX issues outlined in other open systems.

    It would seem in keeping the system a wise course of action is the use of an elevated running temp. My little house has a few times the fin needed at 180 degrees. Because of this I was all to eager to take advantage of 120 water, which still cycled on and off this winter during a 0 degree day and night with 60 MPH winds. It was cold!! The interior of all the storm doors and windows were frozen over. We couldn't see out of the house. :D But inside was nice and warm and the thermostat was still cycling.

    I could manage a mixing valve a lot easier than I could any other options that are apparent to me. It should at least keep the tank and loop under control. Mixing at every point of use would add up too, unfortunately. Thank you, and everyone, again for your info.

  • AlexiaAlexia Posts: 10Member


    I think you both missed tankLESS in the second paragraph. :D If I'm not mistaken, a copper heat exchanger is pretty common among gas fired tankless. The second paragraph should make more sense.
  • You're right...

    I did, and went back and deleted that paragraph from my post. My bad...

    ME
  • WHat happens when you go on vacation?

    The water in the baseboard loop WILL become stagnant. It is NOT the same as a flat plate heat exchanger.

    Best of luck to you, and if anyone starts showing signs of the flu or pneumonia, DO NOT HESITATE TO SEEK MEDICAL ASSISTANCE.

    ME
  • AlexiaAlexia Posts: 10Member


    Vacation is a good question. It wouldn't seem to be any more or any less stagnant or concern than the water heater and every other pipe in the house. What would apply to them would apply to the loop. What would apply to the loop would apply to them.

    Doesn't using a high temp during the heating season seem to eliminate the amplification issue of the loop, and the tank year round for that matter? Outside of the heating season the loop is just a cold water line. During the heating season it would get repeatedly hit with high temp and cold cycles. Or am I way off base here?
  • missed

    the tankless reference! However, the water heater is just one piece of the system. The longer the piping, the larger the system's volume. The larger the volume, the greater the risk - in my opinion. Flushing the system certainly moves the free-roaming bugs on and out, but it's the out and how that's atomized where risk can become a dose.

    To answer a previous question I'd also missed (read when searching for the tankless ref), the 2- to 4-PPM of chlorine in municipal water has no affect on Legionella. Chlorine Dioxide and copper-silver ionization systems are the only treatment systems that actually offer eradication. Chlorine Dioxide dissipates fairly rapidly and, unlike chlorine, it penetrates biofilms. No residual kill-rates however. Copper-silver ionization, on the other hand, does have a very good residual kill-rate and offeres the best protection. When combined with ultrasonic bombardment, a 100% eradication of bacteria, including Legionella is assured. Both systems are widely available in European countries. When I discussed open systems with folks at ISH-Germany, they thought I was trying to pull their collective legs.

    If you asume the free-roaming bugs are there by virtue of hitching a ride from the incoming cold water line only and that they won't colonize the system, then I could see your inclination to scoff at my concerns. However, the reality is that most of the free-roaming bugs are a result of bacterial blooms as nursery cysts burst open spewing forth their contents. Global Pipe has the only recorded live video showing this as it occurs, that I'm aware of, and we included a portion of that clip in the DVD Scalding - Danger Lurks. If you're interested in learning more about the issues, a free copy can be obtained via Wattsreg.com.

    I wonder though: if you'd known about these issues before you installed an open system - would you still have agreed to have one installed? Would you be inclined to divulge the information when selling your home? Let the buyer beware? Should installers and purveyors be liable if they don't reveal the risks before they install/sell? Should they be afforded bankruptcy protection under the circumstances? As incidents like the recent report on open system contamination become more frequent, will home inspectors begin to call them out? Will our national codes wake up and smell the coffee? In due time.
  • AlexiaAlexia Posts: 10Member
    Do it again?

    ========================================================
    From the Contractor Mag. article 656:

    "The conditions necessary for bacterial amplification are as follows:


    A stable, wet environment with a temperature between 68° and 120° F;
    Existence of bio-film to feed and shelter the bacteria;
    Oxygen to allow the bacteria to breath;
    The absence of any material, such as copper, that could suppress bacterial growth; and
    A pH between 5.5 and 9.2

    Unfortunately, through the introduction of plastic tubing as a water transport media, one critical control component — copper — has inadvertently been eliminated from this process. So, in a nutshell, we have given the bacteria the perfect environment for bacterial amplification."
    ======================================================


    Every line in my home, including the open loop, meets every criteria for an amplification zone, at least during the summer, with the exception of one: The pipes are all copper.


    ======================================================
    From: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=201521:

    "At 20 degrees C, L. pneumophila accounted for a low proportion of biofilm flora on polybutylene and chlorinated polyvinyl chloride, but was absent from copper surfaces. The pathogen was most abundant on biofilms on plastics at 40 degrees C, where it accounted for up to 50% of the total biofilm flora. Copper surfaces were inhibitory to total biofouling and included only low numbers of L. pneumophila organisms. The pathogen was able to survive in biofilms on the surface of the plastic materials at 50 degrees C, but was absent from the copper surfaces at the same temperature. L. pneumophila could not be detected in the model system at 60 degrees C. In the presence of copper surfaces, biofilms forming on adjacent control glass surfaces were found to incorporate copper ions which subsequently inhibited colonization of their surfaces. This work suggests that the use of copper tubing in water systems may help to limit the colonization of water systems by L. pneumophila."
    ======================================================


    Legionella is totally absent in copper pipes except at near 40C (104F) where it exists only in small numbers as a small percentage of a small biofilm. At 20C (68F) and 50C (122F) legionella and biofilm is absent.


    =========================================================
    From proposal submitted to the IPC:

    "[...] the introduction of potable cold water into the water heater/space heating heat exchanger combination shall be routed such as to purge the heat exchanger heat source circuit with each and every draw of potable hot water to avoid possible stagnation and potential bacterial amplification."
    ===================================================


    My open loop follows this very principle. The loop contains about 3 or 4 gallons of water easily flushed, 100%, many times a day with clothes washing, dish washing, and showering alone.


    =====================================================
    =====================================================


    From the information so far, I would do it again - I see no reason not to. With the exception of having a gas fired storage water heater I don't see any reason to even elevate my water above 50C But, unfortunately, I do have the tank so it seems pretty wise to shoot for 60C and use a mixing valve. What I would like to be different in my home is to have a copper heat exchanger equipped tankless water heater. But that aint gonna be cheap either. Though a small natural draft, standing pilot model would be that much more attainable, someday, hopefully.

    The info indicates that PEX, plastic, galvanized pipe, and electric storage water heaters are the most threatening legionella concerns in the home, followed by gas fired storage water heaters. Buyer be aware!
  • ChapChap Posts: 42Member
    prepared by?

    The CDA.

    Other studies have indicated that protection is limited to the outer fringes where the biofilm/bacteria come into direct contact with the copper.

    Still other studies have indicated a thorough system flush (in copper systems) should follow repairs to the piping due to dislodging large quantities of biofilm.

    While copper, especially a new copper system, offers limited protection - it is just that - limited.

    The problem still exists.
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