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  1. ContractorDave

    Testing of diesel fuel requirements.

    The 2014 edition of NFPA 25 introduces fuel testing requirements in section 8.3.4 with the rather vague description of "testing for degradation" per ASTM D975‐11b. I read a LinkedIn blog referring to this and how different testing companies have different ideas about what should be tested for in...
  2. ContractorDave

    NFPA 25 2014 HandBook now has all the reports - to what end?

    I've had the Handbook pdf on my desktop for a while but have only had a few cursory looks at it. I'm quite impressed with the level of detail they go into now in explaining the proper use of the standard. I also notice that for the first time in ages they have included actual report forms...
  3. ContractorDave

    Why is the temperature rating of a sprinkler not addressed in NFPA 25?

    Why does chapter 5 not address whether or not a sprinkler head is the correct temperature for its location? They address orientation which assumes it is a sprinkler that has been replaced incorrectly. Why wouldn't this be the same assumption for a high temperature head found in an ordinary...
  4. ContractorDave

    NFPA 25: 4.1.8 Information Sign

    So. NFPA 25: 4.1.8 Information Sign. 4.1.8.1 A permanently marked metal or rigid plastic information sign shall be placed at the system control riser supplying an antifreeze loop, dr y system, preaction system, or auxiliary system control valve. 4.1.8.2 Each sign shall be secured with a...
  5. ContractorDave

    NFPA 25 13.6.2 on backflow preventers

    Hello I sent this off to NFPA25@nfpa.org: Hello I’m trying to understand 13.6.2 13.6.2.1 speaks to the forward flow testing of backflow preventers. A13.6.2.1 starts off by discussing this, then ends with “The tests required by 13.6.2 typically test only for operation of the device under...
  6. ContractorDave

    NFPA 25 HBK - Comments on dry system water delivery to IT. What?

    Frequently when reading code I'll come across a piece that's hard to digest and I'll decide to ask this good forum for an opinion. Sometimes while writing it down here it will suddenly become clear and I won't have to post it. Other times I will post it and get some valuable information. Here's...
  7. ContractorDave

    You don't need to use an affinity law to find pressure at a specific flow.

    Quoting my friend skdesigner from a closed thread (Pump Affinity Laws August 2012) "You don't need to use an affinity law to find pressure at a specific flow." I agree but then what do you use the affinity laws for? NFPA 25 8.3.5.2.1: Theoretical factors for correction to the rated speed...
  8. ContractorDave

    Permissible air loss in a dry pipe system

    I was responding to an article in a trade magazine and I was going to include the sentence from what I thought was NFPA 25 in regards to acceptable air loss in a dry pipe system - I recall from SOMEWHERE something along the lines of "Air loss of more than 10 psi a week shall be investigated and...
  9. ContractorDave

    NFPA 25 Deficiency vs Installation Deficiency

    We've hashed this out before but there's always something new. Here's a fun one: I have an unlisted diesel fire pump (an 80 gpm / 80 ft head end suction Aurora on a small 4kw Yanmar). It's fed from a combination domestic / fire water tank with a float that shuts water off to domestic at a...
  10. ContractorDave

    Engineering requirements for tenant improvements

    As AHJs, when do you draw the line for tenant improvements and require engineered calcs? Regards D A thing moderately good is not so good as it ought to be Thomas Paine www.ykfireprevention.ca
  11. ContractorDave

    Rodding out the heat exchanger (Table 8.1.2 - NFPA 25)

    I Googled it and I asked our rep at the company who does many of our start-ups and commissioning of diesel fire pumps but I haven't come out much more the wiser. Looking at most heat exchangers, this doesn't seem very intuitive. Can anyone share their experiences on this?
  12. ContractorDave

    NFPA 25 2011 ed- Chapter 11 - 11.1.4.2 asks you to verify proper installation?

    "11.1.4.2 The inspection shall verify that all components,including foam concentrate discharge devices and proportioning equipment, are installed in accordance with their listing." I have an inspection coming up on a large foam water sprinkler system - (7) 6" deluge valves - and I thought I'd...
  13. ContractorDave

    NFPA 20 - 5% volume for sump in fuel tank Fig A 11.4.4

    I seem to be getting conflicting explanations for this 5% sump. On the face of it, it would appear that this sump volume is to prevent debris from getting into the fuel line. However my fire pump supplier is saying this is something built into the design of the tank and has more to do with head...
  14. ContractorDave

    Calling as deficiency inadequate drainage?

    If a test required by NFPA 25 can't be performed due to current system conditions, do you call for the repair of the condition as a deficiency? IE: An alarm valve installed in a basement where the floor drain will never be able to take a full flow main drain test. Or an RP on a anti-freeze...
  15. ContractorDave

    NFPA 25 Ch13 When a NO valve is closed, impairment procedures shall be

    Hello The following was sent to NFPA25@NFPA.ORG for clarification but I'd like the forums take on it also please: "There is some ambiguity here: 13.3.1.2 When a normally open valve is closed, the procedures established in Chapter 15 shall be followed. Shouldn’t this be under section...
  16. ContractorDave

    NFPA 13D vs 13R - and AHJ variances that put an installer at risk..

    Scenario: A residential structure is designed as a 3 family dwelling that is basically 3 prefabbed and pre-sprinklered structures that are assembled on site one on top of the other. The local bylaws state "All two family dwellings and multiple family dwellings shall be sprinklered". (That's all...
  17. ContractorDave

    Added file for fire pump question below

    Attached is that ISO Thx Dave
  18. ContractorDave

    Fire pump testing - how might one do the attached example with a PRV?

    Hello I'm doing ITMs on a mine site. There's a fire pump module / trailer with two 2000 gpm pumps fed from tank supplies. I drew up a rather corny looking iso with one system represented. There's a flow meter test loop on the system but there's also a PRV loop that does not have isolation...
  19. ContractorDave

    10 psi per week for loss of air in a dry system?

    I'm looking at an ASFA report for inspection of dry systems where Leaks resulting in air pressure losses greater than 10 psi / week shall (be) located and repaired. I do not see this stated as such anywhere in NFPA 25. 5.2.4.1 states in part: ...to ensure that normal air and water pressures...
  20. ContractorDave

    Wasn't there a time when there was a figure associated with 5.3.1.1.3

    I have a building with 22 year old QR sprinklers that I will send out for UL testing as per 25, 5.3.1.1.1.3. I thought there was a recommendation of how many per 100 or percentage in 25. I sure don't see it now. Thx Dave

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