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Tamper Resistant Flow Switch

Tamper Resistant Flow Switch

Tamper Resistant Flow Switch

(OP)
NFPA 72 Section 6.8.5.11 references flow switches that require a tamper resistant cover.  The tamper resistant screws are not mentioned, but a monitored contact that reports to the FACP.  Typically we do not require this specific type to be installed, nor do we see them in the field.  Is it the intention of 72 to require contact closures on the flow switch covers to help identify possible tampering, or am I missing the ball completely?

RE: Tamper Resistant Flow Switch

as you mentioned most of the covers have the funny looking screws and my guess that meets 72. away form my books for awhile, will post an answer later if someone else has not commented

RE: Tamper Resistant Flow Switch

I have had to have these on a few jobs.  I believe if you contact Potter Electric, they make a device that sends an alarm to the FACP if the flow switch cover is opened.

The last one I saw was on a military project.

Travis Mack
MFP Design, LLC
 

RE: Tamper Resistant Flow Switch

All new flow switches listed for fire protection service have the cover tamper switch. But 6.8.5.11 also reads "Exception No. 2:  
Tamper resistant screws or other approved mechanical means shall be permitted for preventing access to junction boxes and device covers installed outside of buildings." which on the face of it suggests this is no longer allowed inside the building. This appears odd, as I would suggest the device inside is likely to be more secure than one outside. If the intent is to signal the FAP for tampering now, I cannot think of a reason for the exception.  

RE: Tamper Resistant Flow Switch

(OP)
I would agree that equipment outside the building would be subject to 'foul play' before inside devices, and for a flow switch to be on the exterior of the building would be something new (at least here in Kansas City).  I have asked NFPA for a clarification and we'll see what they say.

Thanks for your response lightecho

RE: Tamper Resistant Flow Switch

NightME,

Did you ever hear back From NFPA on this issue?

RE: Tamper Resistant Flow Switch

(OP)
The answer I recieved from NFPA 72 is:

You would need to take into consideration the exceptions at the bottom of the main text and then monitored covers on j boxes outside would not be required if tamper resistant screws were used.
"Exception No. 2:  
Tamper resistant screws or other approved mechanical means shall be permitted for preventing access to junction boxes and device covers installed outside of buildings".


-But it does not really answer my original question.  When I reasked the same question (worded more clearly) they gave me the exact same answer.  Really they where of no help.

It appears that this section only refers to outside devices and not address interior devices.  I have a feeling we are going to have a battle with the local Fire Marshal since it was after the contract was awarded and the 997,000 sq ft bldg was under significant construction before this 'requirement' came up.  Still trying to get everything lined up so that we can educate him a little on the intentions of 72 and tamper resistant devices.

Thank you for your interest

RE: Tamper Resistant Flow Switch

NFPA will go to some lengths at times to avoid clarifying what they have put down in print lest someone mis-interpret a clarification and then hold them responsible.

Just to note:t the tamper switch inside is not meant to be a supervisory signal and is merely tied in with the alarm line back to the FACP. Really, even if you have hundreds of flow switches there is no real additional labor involved.

Regards
Dave

RE: Tamper Resistant Flow Switch

May I clarify that last post a tad ...."and is merely tied in with the alarm line back to the FACP, so that when the cover is removed, a trouble signal occurs." ...

Regards
Dave

RE: Tamper Resistant Flow Switch

In the 2007 edition and proposed 2010 I believe nothing has changed since exceptions 1-2 are clear as to what is permitted for both interior and exterior applications.  The same is true for the 02 edition 6.8.5.10.1

  

"Fire suppression is a failure in prevention"

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