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4. Requirements for fire detection and fire fighting equipment
4.1 Consequences of using water to extinguish fires in storerooms
Water is always used by fire fighting personnel to extinguish fires. Archivists and Librarians have often held the strong conviction that water was as destructive to archives and books as fire.
This view is still held by many records custodians in Europe. However, archivists and librarians in North America accept and, in most cases, enthusiastically endorse the use of automatic sprinkler systems as an integral part of their fire protection system. North American archivists tend to accept the thesis that wet records can be recovered, but burned records cannot. While virtually any wet paper records can be recovered, provided prompt and proper action is taken, effective salvage requires special techniques, facilities, and expert advice. Preplanning for records recovery is essential.
It is important for archivists and librarians to understand that unless there is a specialized fire extinguishing system to control the development and growth of a fire, responding fire fighting forces would have no choice but to attack the fire with fire hoses. In many facilities the quantity of paper fuel involved is such that the fire department would have to fight the fire from a distance under very adverse conditions. This would normally force them to use heavy hose streams having the characteristics of a hydraulic ram. Wide and forceful disruption of the records storage arrangement would be a normal effect of efforts to prevent total destruction. The fire fighters may also take actions that disrupt and damage records that are not burning in order to reach the actual seat of the fire. While properly constructed fire walls would assist a fire department in limiting the size of a fire, all of the records within the fire area would probably be seriously affected by either fire or water from the high pressure streams or both.
When an automatic extinguishing system of proper design is provided, the role of the fire department changes to one of assisting and supplementing the automatic extinguishing system, rather than direct fire attack. The most effective fire protection element and the most economical automatic fire control system for protection of archives is the automatic wet-pipe sprinkler system. Such systems are also the most frequently opposed by archivists and librarians because of their concern with water damage. Three facts ought to dispel much of this concern:
(1) Sprinklers actually constitute a method of fire control involving a minimum rather than a maximum of water.
(2) Each sprinkler operates individually and the operation of any one does not cause the operation of any other sprinkler; therefore, only those sprinklers in the heat of the fire operate and discharge water.
(3) Wet records are recoverable, burned records are not.
(4) The probability of sprinkler operation at a time when no fire exists is insignificant.
Where an archive or library is protected by an automatic sprinkler system, provision of a waterflow alarm that transmits a signal to the fire department on the fusing (opening) of one or more sprinklers eliminates the possibility of a sprinkler operating -undetected and discharging water for a long period of time, excessively wetting the records underneath, even though it had already successfully extinguished the fire. The waterflow alarm feature, in addition to signaling the existence of a fire, will also detect the flow of water in the rare instance of accidental or malicious damage to the system.
The sprinkler system operates only when the fire has reached the point of rapid heat rise and has passed the phase of development where manual fire extinguishing could be expected to be undertaken successfully. Both tests and fire experience have shown that sprinklers can be expected to confine the fire to a relatively small portion of the row of shelving where the fire started. Should action by the fire department still be required by the time they arrive, they could approach the seat of the fire and use small hose streams to quench the remaining fire.
Under normal conditions in a sprinkler protected facility, it is probable that fire would be confined to an area of between 9.3 and 46.4 m². Water damage would consist primarily of superficial wetting of cartons in those areas where cartons were involved or edge and bottom wetting of open file records. The areas of water damage to the degree described above would probably extend about 3.0 to 6.1 m to each side of the area of fire damage. The records on top of the top shelves would be the wettest; those on lower shelves would be shielded from direct impact of water and would be considerably drier. It is expected that total extinguishment and shutdown should take place normally before failure of the corrugated or pressboard cartons. Fire department operations in a sprinklered facility will probably cause only minimum physical disruption. Solid fiberboard (archival) boxes resist water damage to a much greater degree than corrugated cartons.
There are four other types of sprinklers that lend themselves to records and library protection.
(1) The pre-action system is a system in which the sprinkler piping normally is dry, and the control valve opens only when the heat detection devices detect the development of fret It is more expensive and less reliable than a wet-pipe system.
(2) The recycling system is an adaptation of the pre-action sprinkler system with a recycling feature. When the sprinkler or sprinklers have extinguished the fire and the heat drops below a preset temperature (such as 60 degrees Celsius), the detectors cause a timing cycle to start that automatically discontinues the water flow by closing a special valve in about 5 minutes.
The system remains in readiness, and, should the fire redevelop it would cycle and start again. It is somewhat more expensive than the pre-action system.
(3) On-off sprinkler heads. Sprinkler heads are available that have a recycling feature. Installed on wet-pipe sprinkler systems, each head operates individually at a predetermined temperature, but when the temperature drops below the predetermined temperature, the head shuts off. Each head works independently, on and off, depending upon the fire situation in its immediate area. No separate detection system is required. The technology of the on-off heads is relatively new, and long term reliability data are not available.
(4) Dry-pipe sprinkler systems. The sprinkler piping is filled with compressed air. The release of air pressure, as through a fused sprinkler head, allows the water valve to open and supply water to the sprinkler piping. Each head operates independently. Releasing air pressure through a fused sprinkler head takes appreciable time, during which the fire may grow and open additional sprinkler heads. Dry-pipe sprinkler systems are primarily used for protection of unheated areas where freezing may occur.
4.2 Fire fighting agents that do not adversely affect documents
Extinguishing fires by flooding record storage compartments with gas is favored by many archivists and librarians, on the basis that, if no water is applied to a fire, no water damage occurs, and salvage problems are simplified. Two principal gases for this application are Halon 1301 and carbon dioxide.
While water-based agents depend on cooling and quenching, and carbon dioxide depends primarily on oxygen-exclusion, Halon 1301 inhibits burning by chemically interacting with the flame radical. Halon 1301 (bromotrifluoromethane) is a liquified gas under pressure, which is an effective flame inhibitor while at the same time exhibiting low toxic and corrosive properties.
Halon 1301, being a flame inhibitor, is not effective at normal concentrations against smoldering fire. In a records storage facility, it is important that application be undertaken as early as possible in the fire, before it becomes deep-seated. To be effective, it is also important that the system be automatic, total flooding, and employ a properly responsive detection system. It is essential that means be provided to contain the gas without significant leakage for an extended period of time. Halon 1301 systems are relatively expensive, and most installations have been limited to protection of high value collections in modest-sized places (less than 1416 m³). Total extinguishment by Halon 1301 of a fire in a paper storage area is not likely because of the likelihood of smoldering occurring. Prevention of flaming fire pending arrival of the municipal fire department may be adequate. Rapid fire growth would be inhibited in the interim.
Halon 1301 will soon be unavailable. It is one of the family of chlorofluorocarbons that has been banned from sale by 1996 because of their destructive impact on the earth's ozone layer. Chemical companies can be expected to try to develop a replacement for Halon 1301.
Fire extinguishment can also be accomplished by a total flooding carbon dioxide system with a soaking period. Systems for records protection are designed to provide a concentration of 65 per cent in the protected space, to control stratification, and to maintain soaking for 30 minutes. Openings not required for pressure venting must be closed at the time of discharge to avoid loss of carbon dioxide during the soaking period.
Since atmospheres containing fire extinguishing concentrations of carbon dioxide will not sustain life, it could be fatal to be trapped in the flooded space. Ample warning and time delay must be given prior to discharge to allow occupants to escape--from the area to be flooded. A person could not safely leave the area after the discharge starts. For effective fire control, the activation of the carbon dioxide system should be automatic in response to fire, triggered by a properly designed and installed heat detection system.
High expansion foam is another total flooding medium, meaning that it inundates the protected space with the extinguishing agent. The foam surrounds all the materials within the protected area with an aggregate of bubbles, each of which carries a small amount of water. High expansion foam extinguishes fires quickly and easily by filling the entire volume of the storage space. The degree of wetting is low: generally it does not penetrate normal corrugated fiberboard cartons. However, after exposure to foam it is necessary to take corrective drying action on all the materials within the area contacted by the foam.
Total flooding systems require maintaining sufficient foam to submerge the hazard, length of time of coverage of the hazard, and minimum rate of discharge to compensate for breakdown of foam by sprinkler discharge, shrinkage, fire, and other factors. High expansion foam systems require venting, closure of openings through which foam would escape, and maintenance of foam to cover the hazard to ensure control and extinguishment of fires. The rate of application of high expansion foam is high, and a large vent area is needed for the displaced air. Automatic activation of the system is by a heat detection system.
There are a number of factors involved in comparing extinguishing systems. Original cost, reliability, cost of agent, susceptibility to false operation, area of application, damage to records by fire and by extinguishing agent, and consequences of failure are all important factors for consideration. Automatic sprinklers are the most reliable and economic means of controlling fires in records storage areas. Wet-pipe sprinklers with hydraulically designed piping, adequate water supply, and supervised valves are reliable and trouble-free. Cyclic systems, pre-action systems, and dry-pipe systems, provide for assurance against water damage, introduce failure potentials in the system and can slow system functioning in a fire and result in a larger fire to extinguish. In a fire, only sprinklers in the immediate vicinity of the fire are activated.
Gaseous extinguishment has the potential for least damage if all elements perform as designed. Automatic operation of the system and automatic closure of leakage openings is essential to the success of these systems. Neither halon nor carbon dioxide can be expected to extinguish a deep-seated fire condition that would occur if an archives fire were allowed to become well developed before application of the extinguishing gas. Gas leakage through a blocked-open door, a temporary opening, or a fire caused breach could also result in a failure. All materials in the enclosure are equally treated by the gas, whether near the fire or away from the fire. Final extinguishment is usually performed by the fire department using hose streams.
Automatic high expansion foam has the capacity to overcome a well-established fire and in this factor is much superior to gaseous extinguishment and better than sprinklers. Like gaseous extinguishment, high expansion foam will escape through unclosed openings. Also, like gas, all materials in the enclosure are equally exposed to the extinguishing agent. As the foam will dampen cartons, all materials in the enclosure are damaged slightly and must be dried. Final extinguishment by fire department hose streams will probably be -required.
4.3 Fire detection systems
Early warning detectors, known generically as smoke detectors, respond to either the visible (smoke) or invisible (molecular size) products of combustion, or both, produced from the moment of ignition. In a properly engineered installation, these devices can detect a smoldering fire in its low energy stage. Where ignition from a smoldering fire is likely, they can give warning very early in the fire development.
Listed or approved smoke detectors include ionization type, photoelectric beam or spot type, infrared type, etc. It is possible, if the need warrants, that these early warning systems may activate associated fire extinguishing systems. These may be considered as part of the overall system in any important record collection where a smoldering fire is possible.
Total dependence on the combination of smoke detection and hand-held fire extinguisher attack still leaves the facility subject to a major disaster. Dependence solely on an early warning detection system exposes the facility to full fire development before effective efforts can be undertaken.
It is important that smoke detection systems be individually engineered by competent personnel. Where the devices are used, they are installed because of the desire to obtain the earliest possible knowledge of the existence of a fire. The various types of air movements, including stratification caused by heating or other air-handling systems, as well as that provided by the records storage arrangement, are important considerations. It is the best practice that the system be capable of detecting and locating the presence of fire in any portion of the records storage area within the briefest period of time. While the time element specified will directly affect the cost of the system, it will also affect the extent of the damage. Generally, the shorter the time for detection, the higher the cost of the system.
Heat and smoke detectors require a signal transmission system to report the fire to the fire department, sound the local alarm, and/or activate fire suppression systems, ventilation controls, etc., as appropriate.
4.4 Fire extinguishers
Regardless of other types of fire extinguisher systems provided, it is essential that every records storage facility be provided with an adequate supply of well-distributed portable fire extinguishers suitable for extinguishing fires in paper and plastic records. It is desirable that the type of extinguisher provided be the trigger action type in which the flow can be started and stopped by the operator. Gaseous extinguishers are not effective for extinguishing deep-seated fires in paper materials. The presence of the proper extinguishers would enable the working or guard force, on discovering a fire or responding to an alarm from an early warning detection system, to attack and extinguish the fire while it is small, with minimum damage to the records. It is important that staff are properly instructed in the use of small fire extinguishers.
4.5 Managerial responsibilities for fire prevention and protection
Plans developed by the management of archives and libraries to protect the collections, the facility, and personnel from fire should include the following goals:
(a) remove potential causes of fires;
(b) create conditions that impede the spread of fire;
(c) ensure the safety of staff and visitors;
(d) create a fire evacuation plan for particularly valuable record/books;
(e) install fire extinguishing devices that cause the minimum damage to the records while ensuring that the fire is extinguished with the minimum loss.
Every archives and library should have a fire protection plan for their facility. Many of the measures that can be used to protect against fire have been mentioned in this paper.
Management officials also must assume responsibility for developing evacuation plans for staff and visitors. It is not enough to ensure that sufficient exits exist; or that fire doors are kept unlocked and unblocked; or that furniture has not been rearranged to block exits. Evacuation plans should be developed with specific responsibilities assigned to various staff members to ensure that the building is cleared when an alarm is sounded. Evacuation plans should be tested by having unannounced fire drills.
It is also important to work with the local fire department to ensure their cooperation should a fire occur. Providing periodic walk-throughs for fire fighting personnel who would be expected to be called to fight a fire should an alarm go off, can improve their response time. This is particularly important in buildings which have rather complicated internal layouts. The quicker the fire fighter can get to the fire, the less damage there will be to the collections. Fire departments will often agree to provide periodic instruction to staff on the proper techniques for using portable fire extinguishers.
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