See commentary to section 24.2.1.9 ('10 ed). These additives that are intended
to plug small leaks end up clogging small orifices, bind sprinkler parts and
delay or prevent operation. It also says these chemicals harden when exposed to
air which can create an obstruction.
Duane Johnson
-----Original Message-----
From: njarendt tds.net [mailto:[email protected]]
Sent: Wednesday, October 31, 2012 3:47 PM
To: [email protected]
Subject: Re: Sodium Silicate
Several reasons
Sodium silicate is a white powder that is readily soluble in water, producing
an alkaline <http://en.wikipedia.org/wiki/Alkaline> solution. It is one of a
number of related compounds which include sodium
orthosilicate<http://en.wikipedia.org/wiki/Orthosilicate>,
Na4SiO4, sodium
pyrosilicate<http://en.wikipedia.org/w/index.php?title=Pyrosilicate&action=edit&redlink=1>,
Na6Si2O7, and others. All are glassy <http://en.wikipedia.org/wiki/Glassy>,
colourless and dissolve in water.
Sodium silicate is stable in neutral <http://en.wikipedia.org/wiki/PH> and
alkaline <http://en.wikipedia.org/wiki/Alkaline>
solutions<http://en.wikipedia.org/wiki/Solution>.
In acidic <http://en.wikipedia.org/wiki/Acidic> solutions, the
silicate<http://en.wikipedia.org/wiki/Silicate>ion reacts with hydrogen ions to
form silicic acid <http://en.wikipedia.org/wiki/Silicic_acid>, which when
heated and roasted forms silica gel <http://en.wikipedia.org/wiki/Silica_gel>,
a hard, glassy substance.
The absence in the US of mandatory aging tests, whereby PFP systems are made to
undergo system performance tests *after* the aging and humidity exposures, are
at the root of the continued availability, in North
America<http://en.wikipedia.org/wiki/North_America>,
of PFP products that can become inoperable within weeks of installation.
Norm
On Wed, Oct 31, 2012 at 6:08 AM, [email protected]
<[email protected]>wrote:
> Stops up drops and heads. It will collect in low points also and cause
> obstruction.
>
> Sent from my HTC EVO 4G LTE exclusively from Sprint
>
> ----- Reply message -----
> From: "JSM Fire Pro" <[email protected]>
> To: <[email protected]>
> Subject: Sodium Silicate
> Date: Tue, Oct 30, 2012 11:48 PM
>
>
> Why does NFPA 13 not permit this additive for fire sprinkler systems?
>
> Thanks in advance.
>
> J. Scott Mitchell, PE
>
> _______________________________________________
> Sprinklerforum mailing list
> [email protected]
> http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
> -------------- next part -------------- An HTML attachment was
> scrubbed...
> URL: <
> http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attac
> hments/20121031/6d0f685f/attachment.html
> >
> _______________________________________________
> Sprinklerforum mailing list
> [email protected]
> http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
>
--
*If You See Something Suspicious.... Say Something! 1-866-HLS-TIPS.*
Norman Arendt, CHS III, CMAS, PhD, CFEII President Infragard Madison Members
Alliance Middleton Fire District Plan Reviewer and Investigator PCII and CVI
Certified
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20121031/4c02f53e/attachment.html>
_______________________________________________
Sprinklerforum mailing list
[email protected]
http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
_______________________________________________
Sprinklerforum mailing list
[email protected]
http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
