Thanks guys. Wouldn't have thought to look in 72. I would have though that was the how to do it not when to do it standard and I did miss 13.8 in 22. I also find it interesting 22 is 5" when required at 12" from 72. I do see it's an annex vs. body situation though.
Chris Cahill, P.E. Fire Protection Engineer Sentry Fire Protection, Inc. 763-658-4483 763-658-4921 fax Email: [email protected] Mail: P.O. Box 69 Waverly, MN 55390 Location: 4439 Hwy 12 SW Waverly, MN 55390 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, September 24, 2009 10:50 AM To: [email protected] Subject: RE: Tank water alarms NFPA 72 6.8.5 addresses fire alarm system inputs where fire alarm systems are required. Also 5.15.3.3 A supervisory signal-initiating device for other than pressure tanks shall initiate a low-water level signal when the water level falls 300 mm (12 in.). 5.15.4 Water Temperature Supervisory Signal-Initiating Device. A temperature supervisory device for a water storage container exposed to freezing conditions shall initiate two separate and distinctive signals. One signal shall indicate a decrease in water temperature to 4.4°C (40°F) and the other shall indicate its restoration to above 4.4°C (40°F). NFPA 22, 2003 13.8* Sensors. 13.8.1 Provisions shall be made for the installation of sensors in accordance with NFPA72®, National Fire Alarm Code®, for two critical water temperatures and two critical water levels. A.13.8 It is not the intent of this standard to require the electronic supervision of tanks; however, where such supervision is required in accordance with NFPA 72®, National Fire Alarm Code®, the following alarms should be required: (1) Water temperature below 4.4°C (40°F) (2) Return of water temperature to 4.4°C 40°F (3) Water level 76.2 mm (3 in.) (pressure tanks) or 127 mm (5 in.) (all other tanks) below normal (4) Return of water level to normal (5) Pressure in pressure tank 0.48 kPa (10 psi) below normal (6) Pressure in pressure tank 0.48 kPa (10 psi) above normal For your review.................. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Chris Cahill Sent: Thursday, September 24, 2009 11:40 AM To: [email protected] Subject: Tank water alarms Having trouble finding the required alarm points and water levels for tank water supplies. Is monitoring of tank level even required? I have 10% low water alarm in my head but can't source it. Is it a rule of thumb? Is it 10% below tank capacity or 10% below minimal required amount of water? Many tanks are actually a bit bigger than theoretically necessary. Unless I'm missing it in NFPA 22 it appears only a gauge is required. I know auto refill is not required. NFPA 25 doesn't help, it clearly suggests some tanks have monitoring thus a quarterly insp. some don't and a monthly. So if it's just a gauge we are apparently relying on someone actually looking at it and getting it refilled sometime before the fire starts hopefully? Chris Cahill, P.E. Fire Protection Engineer Sentry Fire Protection, Inc. 763-658-4483 763-658-4921 fax Email: [email protected] Mail: P.O. Box 69 Waverly, MN 55390 Location: 4439 Hwy 12 SW Waverly, MN 55390 _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
