Automatic Sprinklers

Don t use sprinklers automatic irrigation systems, such as sub-soil drip pipes that allow water to drip into the soil, make great alternatives to sprinklers, and use far less water. They are especially useful for times when you are out of town. 

Automatic sprinklers have been proven to be the most reliable form of fixed fire protection since their inception 100 years ago. This favorable record allows employers the opportunity to purchase fire insurance at reduced rates if they install sprinklers. Automatic sprinklers are needed anywhere there is a combustible occupancy and where combustible building materials are used. 

If an ethyl ether fire occurs, carbon dioxide, carbon tetrachloride, and dry chemical fire extinguishers meeting National Eire Prevention Association Code 1 and 2 requirements may be used successhiUy (23). Water may also be effectively appHed (see Plant safety). Hose streams played into open tanks of burning ethyl ether serve only to scatter the Hquid and spread the fire. However, ether fires may be extinguished by a high pressure water spray that cools the burning surface and smothers the fire. Automatic sprinklers and deluge systems are also effective. 

Started to rise from the reaction, causing the vessel bottom head to fail at the weld seam. The force from the escaping gases propelled the tank into the ceiling and overhead structural steel. A small fire erupted which was quickly brought under control by the automatic sprinkler system. Even though the chemists had reviewed the chemistry and did not anticipate any problems, use testing could have identified this problem in the laboratory rather than the plant. 

Design ventilation system to keep flammable concentration below lower flammable limit Provide on-line flammable gas detection and activation of inerting system Install automatic sprinkler system Install deflagration vents... 

Provide automatic sprinkler system/inerting gas Provide deflagration vents Provide deflagration suppression system Monitor flammable atmosphere/fire Provide nitrogen blocks (nitrogen injection to stop flame propagation) or other explosion isolation measures... 

Provide automatic sprinkler system Use deflagration vents... 

Provide automatic area sprinkler/deluge protection... 

Gas storage cabinets are designed to contain one to four gas cylinders. The cylinders are connected to a gas distribution system which is also contained in the cabinet. Very sophisticated systems are available from cabinet manufacturers. These may include automatic or semiautomatic change-over capabilities, fire sprinklers, purging systems, and gas detection systems which may include alarms and automatic shutoff. Point-of-use scrubbers may also be incorporated into the design, depending on the gas being used (see Fig. 10.43). 

Regarding fires, water is the primary extinguishing agent, and it should be available in adequate supply and pressure at all of the locations in the plant. The layout for various types of installations and the appropriate recommendations are found in the standards of the National Fire Protection Association. Fire hydrants, hose lines, automatic sprinkler and water spray systems should all be a part of the permanent equipment facilities of the plant. 

Sprinkler and water spray installations-Many process and storage area buildings should be protected by automatic sprinkler systems. The size and arrangement for water supply are dependent upon the nature of the hazard and the degree of protection desired. Water spray installations are particularly adapted for cooling uninsulated steel structures, elevated pipe lines, vessels, spheres, and similar plant installations. 

Automatic sprinkler systems have the great advantage that they are comparatively simple in concept and operate automatically, whether or not there are people present on the premises. Water is supplied from the public mains or tanks and pumps into a network of distribution pipes at ceiling level, which covers the whole premises. Water is discharged through nozzles or heads sited at regular intervals in the pipework, which are normally sealed with a he at-sensitive device. 

Calculate the relative number of atoms of each element contained in each of the following alloys (a) Wood s metal, which is a low-melting-point alloy used to trigger automatic sprinkler systems and is 12.5% tin, 12.5% cadmium, and 24% lead by mass in bismuth (b) a steel that is 1.75% by mass carbon in iron. 

Automatically operated for general protection, e.g. sprinklers, or for special-risk protection, e.g. carbon dioxide installations. 

The term engineered safety covers the provision in the design of control systems, alarms, trips, pressure-relief devices, automatic shut-down systems, duplication of key equipment services and fire-fighting equipment, sprinkler systems and blast walls, to contain any fire or explosion. 

I. Deviation from these distances requires l pro tective installations such as fixed focm system-., water spray, automatic sprinklers, fire-system grading yf 4 or better, or superior construction. 

Question 15.3 How Does an Automatic Fire Sprinkler Head Operate ... 

Reliable Model ZX-QR-INST Pendent Horizontal Sidewall Quick Response Institutional Sprinkler, Reliable Automatic Sprinkler Co., Inc., http //www.reliablesprinkler.com/sprinklr/137c.htm... 

An Introduction to Automatic Fire Sprinklers, Part 1. Nick Artim, WAAC Newsletter 16 (3) (Sept. 1994), 20,... 

Automatic Sprinkler Corporation of America, 1000 Edgerton Road, Broadview Heights, OH 44147... 

Pilotex Ultra High Speed Deluge Fire Protection for Munitions Explosives Pyrotechnics Gary A. Fadorsen, "Automatic" Sprinkler Corporation of Amerloa... 

Army Research, Development and Engineering Center, 269 Automatic Sprinkler Corporation of America, 200 Black Veatch,... 

Bryan, J. L., Automatic Sprinkler and Standpipe Systems. NFPA, Quincy, MA., 1976. 

Warehouses are normally considered low risk occupancies unless high value or critical components are stored. Some high valve components normally overlooked in warehouses are diamond (industrial grade) studded drill bits or critical process control computer boards. In these cases the economic benefits of installing an automatic sprinkler system should be investigated. 

NFPA 13 - Standard for the Installation and Maintenance of Automatic Fire Sprinkler Systems... 

Measures to reduce the impact of fire include active and passive systems. Active systems include automatic sprinkler, water deluge, water mist, gaseous agent, dry chemical, foam, and standpipe handle systems. Passive protection is provided by fire resistive construction, including spray-applied or cementitious fireproofing of steel, concrete/masonry construction, and water-filled steel columns. Chapter 7 provides details on the design of fire protection systems. 

Containment systems are also used in conjunction with an automatic foam-water sprinkler/deluge system where rapid fire extinguishment is expected. 

The most widely used heat detector is the automatic sprinkler head. 

The principal difference between a pre-action system and a standard dry pipe system is that in the pre-action system, the water supply valve is actuated independently of the opening of the sprinklers. The water supply valve is opened by the operation of an automatic fire detection system, which immediately allows water to enter the overhead piping. Then, when the fire generates enough heat to fuse the sprinkler head, water is immediately discharged on the fire as with a wet pipe system. This system reduces the inherent time lag of a dry pipe system, but can still be used in unheated areas. An example of a pre-action system is shown in Figure 7-26. 

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