Water mist protection for forced ventilation interstitial spaces

Patent metadata

Field	Value
Publication number	US-11207553-B2
Application number	US-201916538346-A
Country	US
Kind code	B2
Filing date	Aug 12, 2019
Priority date	Feb 14, 2015
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

Water mist fire protection systems and methods for the protection of data centers having a raised floor defining an interstitial space beneath the floor. The systems and methods include the location of a plurality of automatic water mist nozzles above and/or beneath the floor to generate a water mist for effectively addressing a fire in the presence of a flow of forced air ventilation through the interstitial space. The systems and methods of water mist fire protection include the interconnection of the automatic water mist nozzles to a water supply to provide for dry pipe or preaction systems and methods. Water mist fire protection of data centers using fire propagating cable is also provided.

First claim

What is claimed is:

1. A method of water mist fire protection, comprising:
locating a plurality of automatic water mist nozzles so that the plurality of automatic water mist nozzles are at least one of above a raised floor of a data center or below the raised floor of the data center; the plurality of automatic water mist nozzles are upright, have a nozzle-to-nozzle spacing greater than or equal to 6 feet by 6 feet and less than or equal to 12 feet by 12 feet, and have a diffuser of each automatic water mist nozzle spaced less than or equal to 3 inches from the floor, the floor disposed above a deck of the data center at no more than a maximum distance of 3.28 feet to define an interstitial space therebetween, at least one cable tray disposed between the floor and the deck at a distance of no less than 12 inches from the floor, each diffuser spaced less than or equal to 12 inches from an elongated edge of the at least one cable tray, the plurality of automatic water mist nozzles comprising a minimum of four automatic water mist nozzles per design area;
wherein locating the plurality of automatic water mist nozzles includes locating the plurality of automatic water mist nozzles below the raised floor in which each automatic water mist nozzle includes a frame body having an inlet for receipt of water, an outlet with a passageway extending between the inlet and the outlet to define a nominal K-Factor of less than 1 gpm/(psi) 1/2 , a seal assembly, a thermally responsive trigger to support the seal assembly in the outlet; and
interconnecting the automatic water mist nozzles to a water supply to generate a water mist to address a fire in the at least one above or below the raised floor in the presence of at least one of: (i) a continuous flow of air through the interstitial space, (ii) fire-propagating cable in the at least one cable tray, and (iii) a fluid delivery delay from the water supply to the plurality of automatic water mist nozzles.

2. The method of claim 1 , wherein the diffuser coupled to the frame body and spaced from the outlet, the diffuser being a planar member with a central portion axially aligned with the passageway and an outer peripheral portion circumscribed about the central portion to define a substantially circular periphery, the outer peripheral portion including a plurality of spaced apart tines to define a plurality of open ended slots formed between the tines and extending radially inward at an equal distance, the frame body including a pair of frame arms diametrically opposed about the outlet to support the diffuser spaced from the outlet.

3. The method of claim 1 , wherein locating the plurality of automatic water mist nozzles includes locating the plurality of automatic water mist nozzles relative to at least one below-the-floor cable tray that includes the fire-propagating cable.

4. The method of claim 1 , wherein locating the plurality of automatic water mist nozzles includes locating at least one automatic water mist nozzle directly beneath a floor grate region of the raised floor, the at least one automatic water mist nozzle being no further inset than a maximum 2 in. (51 mm.) from a lateral edge of the floor grate region.

5. The method of claim 1 , wherein locating the plurality of automatic water mist nozzles includes spacing the plurality of automatic water mist nozzles such that each nozzle is not directly above the at least one below-the-floor cable tray.

6. The method of claim 1 , wherein the plurality of automatic water mist nozzles is designed with a working pressure ranging from 110 to 250 psi.

7. The method of claim 1 , wherein locating the plurality of nozzles includes installing a group of nozzles to provide for localized application and protection of at least one below-the-floor cable tray, the group of nozzles being in a pendent configuration with a nozzle-to-nozzle spacing ranging from a minimum 6 ft.×6 ft. (1.8 m×1.8 in) to 8 ft.×8 ft. (2.6 in×2.6 m) with a diffuser at a diffuser-to-floor distance of no more than a maximum of 7.75 in. (19.7 cm.) and spaced no more than 12 in. (30.6 cm.) from an elongated edge of at least one below-the-floor cable tray such that the group of nozzles is not directly above the at least one below-the-floor cable tray.

8. The method of claim 1 , wherein locating the plurality of nozzles includes installing the plurality of nozzles above the floor and beneath the ceiling.

9. The method of claim 1 , wherein locating the plurality of nozzles includes locating the plurality of nozzles above the floor and beneath the ceiling by installing the nozzles in a pendent configuration, each diffuser defining a diffuser-to-ceiling distance of 1.75 in. to 4 in. (45 mm to 102 mm).

10. The method of claim 1 , comprising:
locating at least one automatic water mist nozzle beneath a ceiling grate.

11. The method of claim 1 , comprising:
interconnecting the plurality of automatic water mist nozzles to the water supply by interconnecting a fluid control valve between the water supply and the plurality of automatic water mist nozzles.

12. The method of claim 11 , comprising:
interconnecting the fluid control valve by providing for a dry network of pipes interconnecting the plurality of nozzles to the fluid control valve.

13. The method of claim 11 , comprising:
interconnecting the fluid control valve by providing for a dry network of pipes that defines a fluid delivery delay time of no more than 30 seconds.

14. The method of claim 1 , comprising:
interconnecting a fluid control valve with a detector for detecting a fire to operate the fluid control valve before actuation of any one of the plurality of automatic water mist nozzles.

15. The method of claim 1 , comprising:
at least one diffuser is a planar member with a central portion axially aligned with the passageway and an outer peripheral portion circumscribed about the central portion to define a substantially circular periphery, the peripheral portion including a plurality of spaced apart tines to define a plurality of open ended slots formed therebetween extending radially inward at an equal distance, and wherein the frame body includes a pair of frame arms diametrically opposed about the outlet to support the diffuser spaced from the outlet.

16. The method of claim 1 , comprising:
providing the continuous flow of air using a ventilation system while addressing the fire.

17. The method of claim 1 , comprising:
each diffuser disperses the water mist to address the fire.

18. The method of claim 1 , comprising:
operating the plurality of automatic water mist nozzles as a wet pipe system.

19. The method of claim 1 , comprising:
detecting the fire using one or more fire detectors.

Assignees

• Tyco Fire Products Lp
• Lpg Tecn En Extincion De Incendios S L

Inventors

• Cutting Sean E
• Bosch Alex Palau

Classifications

• A62C3/00

  Fire prevention, containment or extinguishing specially adapted for particular objects or places ({in oil wells E21B29/08, A62C35/00; in mines or tunnels E21F5/00} ; for nuclear reactors G21C9/04) · CPC title

• A62C35/58

  Pipe-line systems · CPC title

• A62C99/0072

  using sprayed or atomised water · CPC title

• H02G3/0412

  Heat or fire protective means (for fire in electric circuits A62C3/16) · CPC title

• A62C3/16 Primary

  in electrical installations, e.g. cableways · CPC title