Sprinkler system types

Sprinkler system types, water supply sources, and special occupancy conditions and building features affecting system operation. 

If sprinklers are required, or if the sprinkler system is to be modified, such work should only be performed by a company certified to do it. Fire extinguishers are almost always required. The number of them, their placement, and the types needed are matters to be discussed with fiire officials. Extinguishers should be regularly serviced by qualified specialists. 

There are four basic types of sprinkler systems wet pipes, dry pipes, pre-action, and deluge. These are described in the following sections. 

In open process structures or grade level process areas, deluge or water spray nozzles should be of the open type to ensure rapid actuation and to combat the effects of wind. For enclosed structures, closed head sprinkler systems can be used. 

Preplans are similar to floor plans except they will often show features on the outside of the building in addition to the floor plan, although they may have somewhat less detail on the interior of the building. Preplans are frequently made for businesses, churches, and similar types of commercial buildings. These plans are often carried on the trucks for reference by the crews at an incident. A preplan may include information on access roads around the building, connections to sprinkler systems, location of gas or bulk material storage, locations of fire hydrants, information on alarm systems in the building, and other critical information for the crews. 

OS Y Valve A type of outside screw and yoke valve used on piping or in pits connected to sprinkler systems. The position of the stem shows the valve to be eidier open or closed. Osteroporosis a condition in which bones become very fragile. 

Pre-action System A type of automatic sprinkler system in which thennostatic devices are employed to charge the system with water before individual sprinkler heads are fused. 

A wide variety of sensing and initiating devices are available that can detect heat, smoke, radiant energy, and fire gas products. These devices should be selected based upon the type of fire anticipated. Additionally, sprinkler system water flow, activation of other extinguishing systems, and manual fire alarm pull stations can also be used to initiate an alarm signal. 

What type of sprinkler system does code permit ... 

There are two different types of water sprinkler systems, wet-pipe and dry-pipe. The lines leading to the sprinkler heads are full of water in a wet-pipe system so that water will be discharged immediately from an open sprinkler head, while in a dry-pipe system, the lines are full of air under pressure instead of water. This latter type of unit should be used where the temperature is not maintained above freezing at aU times. Both types of systems include a main control valve which is designed not only to supply water to the sprinkler heads but also to provide a mechanism to cause an alarm to sound. The valves also usually provide a visual indication of whether they are open or closed. Except during maintenance, they should be in the open position. There are a number of design features for these valves which are beyond the scope of this document, except to note that some are intended to avoid false alarms due to surges or variations in the water supply pressure to the system. 

Is there a suppression system Yes El NoD If yes, describe type, layout, capability, etc. Buildings and 6581 are provided with automatic, fire protection sprinkler systems throughout, except the Zone 1 SCBs and Zone 2A where water sprinklers would create a hazard. Zone 2A is equipped with manual AliW fire suppression systems. The Zone 1... 

Sprinklers—For types, orifice sizes, and temperature ratings, see the sprinkler head section of the data book. Sprinklers are spaced to cover a design-required floor area (from 36 to 200 square feet) as designated by the authorities indicated in system piping. 

In general, sprinkler systems distribute extinguishing agents to the locations where fires occurs. Sprinkler heads operate independently and determine when they should release the extinguishing agent Placement of sprinkler heads, type of head, appropriate agent, and proper maintenance and testing are essential to the success of a system. 

Components The main components of a sprinkler system are piping, sprinkler heads, and hangers. Piping distributes water throughout the system. Its main components are risers (major vertical pipes), cross-mains, and branches. Hangers of various types support the components. The branches extend from the cross-mains and sprinkler heads attach to branches. There are many kinds of sprinkler heads. Their features can affect how quickly they open, the spray pattern and distribution of water. Fusible links activate most sprinkler heads. The sprinkler code (see note 12) contains standards for all system components. 

Analyze the fire loads and fire controls. Determine if com-partmentation is adequate. Analyze water supplies for adequacy at all locations where there is a need for extinguishing water or emergency showers. Consider the value of sprinkler systems and the type best suited to each location. 

The System 80+ Standard Design is designed to preclude water spray from the fire protection system onto safety-related equipment. The sprinkler systems protecting the safety-related equipment is of the automatic sprinkler type. Actuation of these sprinkler systems requires the opening of the fusible link sprinkler heads and detection by combustible-products and/or heat detectors. In addition, the operator has the capability of isolating flow from the control room by isolating the Sub-sphere Building headers or, locally by manual isolation valves. 

Sprinkler systems have been graded by the FOC according to the number and type of water supply ... 

Four types of sprinkler systems are available wet-pipe, dry-pipe, alternate and pre-action. A wet-pipe system can only be used in premises not subject to frost or ambient temperatures above 70 C. A dry-pipe system is only suitable in premises subject to continuous temperatures below 0 C or above 70 C. An alternate system which enables either wet or dry operation to be selected is suitable in premises subject to freezing during cold weather. Finally a pre-action system, which is a system with a separate heat or smoke detector that allows water into the sprinkler pipework before the first head operates, should only be used where none of the others is suitable. 

A variety of valves are required on a sprinkler system. There must be a main stop valve which on a wet system must be locked open, conveniently placed and fitted with an approved sign. Downstream of this is an alarm valve which opens when a demand is put on the system and also provides a flow to actuate the alarm. Other valves include a drain valve which allows the system to be drained and tests to be carried out on the system and a test valve which simulates the operation of a sprinkler head and enables the operation of the alarm valve and the alarm to be tested. Dry systems and alternate wet/dry systems require further valves. The principal valves in the control units of various types of sprinkler installation are summarised in Table 25.8. 

The fryers and cooking apparatus found in cafeterias will most likely be protected by kitchen hood systems. NFPA 17 Standard for Dry Chemical Extinguishing Systems and NFPA 17A Standard for Wet Chemical Extinguishing Systems will apply depending on the type of agent deployed by the system. Jones (2009) explains these systems and their requirements by comparing th with sprinkler systems, in that... 

An alloy consisting of 24% indium and 76% gallium is liquid at room temperature. Low-melting tin-bismuth alloys contain indium. They are used for safety fuses, in fire-alarm boxes and in sprinkler systems. Also indium alloys are used as solders for printed circuit boards. Indium alloys are easily composed for a specified melting range. Alloys of this type are used to give a signal dear for the Christmas ham or turkey to be taken out from the oven. 

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