Main principles of fire protection in libraries and archives: a ramp study

<> 3. Fire prevention measures

3.1 Stabilizing the environmental conditions in all rooms of libraries and archives
From the standpoint of fire safety, building systems which maintain the environmental conditions in the building should meet the following standards:
(a) Climate influences the selection of building environmental systems. for example, in hot climates it is much more important to provide fully conditioned storage areas in order to mitigate the impact of the external environment.
(b) Restoration, preservation, and duplication laboratories must have their own, separate ventilation system; so should technical service areas of a building, such as boiler rooms, repair shops, workshops, etc.
(c) the air conditioning system should operate with a minimum amount of outside air to reduce the amount of particulate matter (dust) introduced into a storage area.
(d) the emergency smoke-evacuation ducts should have a cross -sectional area which is not less than 0.2 per cent of the floorspace of the room affected.
3.2 Design approaches to ensure the fire safety of library and archives buildings. General requirements.
Buildings housing libraries and archives are either initially designed and constructed as a library or archive or are buildings which were originally used for another purpose and later adapted for use as a library or archive. It is obviously more difficult to introduce the proper fire protection measures into a building not designed as a library or archives. The building which has been adapted to its new use may not even meet the requirements for a fire-resistive building in which the structural elements, including walls, partitions, columns, floors, and roofs are of noncombustible or limited combustible materials.
The interior layout of the rooms in buildings, both specialized library and archives facilities and those adapted to those purposes, include enfilade layouts, corridor-type arrangements, hall arrangements, sectional arrangements, and compound layouts. A hall arrangement is seldom used except where former churches or theaters have been adapted as archives and library buildings. An enfilade arrangement is also usually limited to adapted buildings, e.g., former palaces of the 16th or 17th centuries. A corridor-type layout was typically used in the design of early Soviet archives buildings. This functionally unsuccessful design was later discarded. A sectional layout provides for designing modules that are repeated throughout the building design. Designs which mix elements of several of these types of designs are most commonly used in modern designs for libraries and archives. The type of interior layout used in the design, determine the placing of firewalls within the building which divide the building into fire rated sections and compartments.
Library and archives buildings which are specifically designed to serve those purposes are best able to blend functional operational requirements and fire protection requirements. These designs often use the principle of dividing the building into functional zones which attempt to reduce the distance that must be traveled by the archivist or librarian to bring requested materials to researchers while at the same time restricting visitors to limited areas of the building.
Compartmentalization into functional zones also aids architects and engineers to design into the building various fire protection measures. The architectural design will separate the records storage units from other areas of the building. The walls and floors will be of noncombustible, fire-resistant construction. The design will provide the necessary minimum resistance to fire and fire hose streams for structural consideration and variations in quality of materials and workmanship. Walls must have sufficient lateral strength to withstand impact due to collapsing structural elements, toppling machinery or building equipment.
Most modern designs will also separate restoration, preservation and duplication laboratories from storerooms and from areas where visitors are normally located. The risk of fire is greater in laboratories by the nature of the work going on there. Therefore, they are not only physically separated, they also have separate ventilation systems and may have special explosion proof storage containers for the various chemicals being used in the laboratory. All of the countries surveyed had developed standards limiting the amount of explosive and flammable chemicals that could be stored in one place and specified how the chemicals were to be stored. The laboratory areas will have fire walls aimed at containing any fire that might start there and prevent it from spreading to other areas of the building. From a practical standpoint, it would seem sensible to break laboratory areas up into a series of rooms rather than one or two very large rooms where all of the laboratory processes are carried out. The increased number of laboratory rooms offers greater opportunity for confining a fire to one room and thus limiting the damage.
Designers must also be aware of the requirements to provide fire exits for visitors and staff from the various areas of the building. Fire code requirements vary from country to country and from locality to locality within a country. Architects will be required to design a building with the number and type of exits as specified by the local fire code. These requirements, which are usually based on the size of a space to be evacuated, the usual number of people occupying the space, the type of fire suppression systems incorporated into the building, type of building materials used, etc., will provide sufficient evacuation routes to allow safe egress from the building.
In some countries evacuation requirements provided that any zone within a building where significant numbers of the public congregate must be equipped with two exits where the distance from the remotest point within the space to the exit does not exceed the rated value of E= 1.5P, where E is a distance between the remotest two exits, and P is the perimeter of the hall. The placing of the exits should assure that the evacuation paths do not cross each other. Halls and corridors should be sufficiently wide and straight to enable personnel evacuation to occur easily and for fire fighting personnel and their equipment to reach the site of the fire. The requirement for exits having independent evacuation paths help the architect define the size and positioning of the reading rooms and halls for a library or archives. Since attendance can vary greatly depending on the time of year, exhibits, and other special events, serious consideration should be given to the maximum number of people who might expect to be in the building at any given time when planning the capacity of exits. In every country, fire code requirements guide architects as they design library and archives buildings.
When designing the records storage areas of libraries and archives, architects must also incorporate fire protection requirements. In the former Soviet Union, for example, each storeroom must be separated by fire walls into fire zones which do not exceed 600m² and which have at least two exits. If only one exit is available then the size of the storeroom should be limited to 70 m². Assuming there are no windows in the storerooms, legal requirements also call for exhaust ducts for smoke removal which should be provided with remotely controlled valves. The distance between the valve and the farthest point in the room should not exceed 15 m. The ducts and surrounding structures should be designed to be fire-resistive for at least one hour.
Some library and archives building designs incorporate the use of toboggans in the storerooms to be used to evacuate books or documents during a fire. If toboggans are to be used, the end of the toboggan must terminate within the building to avoid an influx of fresh air which would provide oxygen for the fire. A hatch can be provided on each floor to allow for evacuating materials from that floor. The termination point of the toboggan must be easily accessible to personnel and trucks so the materials can be assembled and taken away to safety. If evacuation of documents is part of a facilities fire protection plan, then toboggans become an essential design element since elevators are switched off in case of fire and stairwells are to be used for the evacuation of staff and visitors and for the fire fighting personnel.
Computer rooms, even those located in buildings other than libraries and archives, have many of the same design and construction requirements as libraries and archives. Most businesses view their computers in the same protective way archivists and librarians view their holdings. Floors and walls should be of noncombustible materials, and they should be constructed using fire-resistant techniques. Traditionally recognized constructions meeting these requirements use reinforced concrete with steel rods at least 13 mm in diameter spaced 152 mm on center and running at right angles in both directions. Rods should be securely wired at intersections not over 305 mm apart in both directions and installed centrally in the wall or panel. Alternatively, construction could consist of a structural steel frame protected with at least 102 mm of concrete, brickwork, or its equivalent tied with steel ties or wire mesh. Firewalls used to isolate the computer centre. Computer centres were usually constructed using techniques which sought to ensure the area was water tight to prevent damage to computers from water used to fight fires in other parts of the building.
The air conditioning ducts used in computer centres should be fabricated of noncombustible materials. If the underfloor space is used as a plenum ventilation chamber for direct air supply into the computer centre, then the underfloor space must be divided into separate fire zones by using firewalls. Without this prevention technique, fire could easily spread from one area to another under the floor.
Multistoried libraries and archives add other fire protection requirements. Smoke evacuation becomes a very important problem to be dealt with. Smoke evacuation systems must keep smoke out of stairwells being used to evacuate personnel from the building and remove smoke from corridors. Properly enclosed stairways equipped with fire doors will prevent the spread of fire, smoke, and heat from one level to another. Elevator shafts, dumb-waiters, and all other vertical openings through the structure should also be safeguarded. Air-handling systems (ventilation, heating, and cooling) should be constructed and equipped to prevent the passage of smoke, heat, and fire from one area to another or from one level to another.
3.2.1 Fire-resistance requirements for structural elements of archives and library buildings
Each country has developed standards for fire-resistant structural elements in buildings and many have developed special requirements for archives and libraries. To apply the standards, it is essential, in addition to any special fire risks posed by laboratories or other technical support areas, to know the fire loading of the archival materials or books. The extension of the fire and the extent of damage would be directly related to the total quantity of combustibles involved. The severity of a fire is approximately 1 hour for 49 kg/m² of gross weight of combustibles involved. The weight of paper in a typical records storage area is equivalent to approximately 49 kg/m² for each shelf height of storage. A records storage area with records stored seven (7) shelves high contains approximately 342 kg/m² of floor area. The Council for Mutual Economic Assistance (CMEA STD. No. 466-77) also provides procedures for determining the fire loading of various buildings. Unless fire development is stopped by either manual or automatic fire extinguishment, the entire records storage in one room or floor could quickly become engulfed in fire. There are no traditional types of fire-resistant construction capable of withstanding the total impact of burnout.
Fire walls are used in construction to keep fires confined to particular areas of a building for specified periods of time. For example, in the former Soviet Union the fire resistance time limit for firewalls and fireproof ceiling/floor panels installed in storerooms containing paper-based documents is two (2) hours, while doors are rated for 0.6 hour. In the United Kingdom the time limit for the same structures is set at four (4) hours. Fire resistance for storerooms containing magnetic storage media are rated anywhere from 0.75 to six (6) hours in different countries.
In addition, consideration should be given to the proper selection of interior finishes and furnishings. Highly flammable wall and ceiling finishes should be avoided. Local fire code requirements usually specify minimum requirements for interior finish materials.
3.2.2 Buildings and Accommodations Adapted for Libraries and Archives
Adapting an existing building for use as a library or archives is usually a last resort for archivists and librarians. If adaptation is being considered, a great deal of study will be involved to determine whether it is possible to adapt the building to the new use. Obviously, such non-fire related issues such as quantity and type of floor space and its functionality must be evaluated.
Historical buildings or architectural memorials are the most difficult facilities to adapt for archives or library use. It is usually impossible to alter the interior layout or to change doors, finishes, etc., in such buildings. Use of very old buildings, or even those classified as ancient, while often proposed for archives or library use, present very great difficulties. It is sometimes extremely difficult if not impossible to determine floor load capacity, what materials were used in constructing the building, and the fire resistance of partitions, etc.
If a building has been determined to be functionally appropriate as an archives or library, the basic elements of fire safety must also be determined. Analysis must include the wall material and thickness, ceiling/floor panel materials and thickness, window casements, doors, and structural elements used in the building. Wooden structural elements were often used in ancient buildings. Historical edifices often used elaborately carved and painted interior finishes made of wood. These elements should be treated with a fire retardant substance which will not produce gases harmful to the collections. More importantly, however, is treatment of the wooden beams which were often used to support older buildings.
Basements create problems for fire extinguishment and safety of life in event of fire. These problems are greatly magnified if loss of power impairs ventilating systems. Alternative means for permitting the escape of heat and smoke should be provided. Provisions should be made for the safe emergency evacuation of people as well as for access by the fire department to the fire area.
Standards in the former Soviet Union specify that basement rooms which adjoin exterior walls should not exceed 3000 m² with a width not over 30 m. Exterior walls should have windows or specially installed "knockout" panels to allow personnel to escape the area and fire fighting personnel to enter. The window should be 0.75 x 1.2 m, with the total area of the window openings equal to 0.2 per cent of the total floor area.
The ceiling/floor panel above the basement should be made fireproof. Two self-contained external stairways which provide access for fire fighting personnel to the basement should be located at opposite ends of the building. If it is impossible to exit the building directly from the basement, and exiting is possible only by way of the general purpose internal stairways, the door leading from the basement should be provided with an airlock vestibule having an positive pressure of 20 Pa (i.e. 2 kgf/m²). The airlock vestibules and the staircases must be enclosed by firewalls.
While adapted buildings may be fitted with a variety of fire protection measures, the best protection for archival and library collections in the long run is to transfer them as soon as possible to a building specially designed for their protection.
3.3 Fire prevention requirements for building support systems and equipment in libraries and archives
Requirements for fire safety of building systems are normally specified by standards promulgated in all developed countries. These systems, which include ventilation, heating, and cooling, are integrated into the overall building structure. Their fire-resistance requirements must be determined as part of the overall fire resistance requirements for the construction of the building.
In some cases the support equipment may be an element of the building structure. For example, in some archives and libraries the part of the building used to house the records or books is only a shell. The metal stacks are self-supporting and extend through several floors of the building. The storeroom floors are merely platforms that provide a walkway through the storerooms. This results in slot-like openings between the storerooms and the walkways, permitting a rapid, uninterrupted upward flow of air, heat, smoke, and flames. This system was used in an archives building constructed in 1886 in Moscow. More recently, some larger archives and libraries have installed horizontal or vertical conveyer systems to move materials from one part of the building to another. In some instances these systems may penetrate firewalls and fireproof ceiling/floor panels.
3.3.1 Forced ventilation and air heating systems
Buildings equipped with air conditioning and ventilation systems have ducts that must pass through firewalls within the building. Any break in a firewall increases the chance of fire spreading through that break. In some instances the duct itself has been weakened sufficiently by fire that it has broken allowing the fire to spread to adjacent areas.
Air ducts should be made of non-combustible materials which provide low heat conduction properties. This is especially important at the point where the duct intersects with firewalls and fireproof ceiling/floor panels. Where the duct is carried through the wall, the holes should be made as small as practicable, the duct provided with a close fitting noncombustible sleeve, and the space around the inside of the sleeve completely filled with approved, fire-resistant material. Ducts should be equipped with automatic fire dampers and fan shutoffs. The ducts should also be kept clean to prevent the buildup of dust which could help spread fire. The building should also have a separate smoke evacuation duct system that is independent from the main building ventilation system.
3.3.2 Requirements for electrical equipment
The electric wiring running through a library or archives building must be airtight. Flush wiring is preferable in new buildings; in old or adapted buildings, the electrical wire should be in conduit. Wiring should be grounded and protected from short-circuits by means of fuses.
Lighting is always a possible fire hazard, more so in some areas or locations than in others. Lighting protection can be more effectively and economically incorporated in the course of new construction than as an afterthought.
Fixed lighting should provide sufficient illumination within a storeroom so that temporary lighting fixtures are unnecessary. Lighting should be limited to vapour-proof or explosion-proof lamps controlled by a 2-pole switch equipped with a pilot light outside the storeroom. Light fixtures should be placed at least 0.5 m from the documents or books. Emergency lighting should be provided with its own independent power source.
Special electrical standards exist for wiring located in wet rooms such as restoration laboratories, fume hoods, duplication laboratories where film developing occurs, and in various other specialized laboratories.
Electrical equipment should be maintained regularly. All equipment should be checked routinely for malfunctions and extension cords should never be used.
3.3.3 Requirements for installation of transportation equipment in archives and libraries
Horizontal and vertical transportation systems should have their own fire protection system. Vertical transportation systems, which include elevators/lifts, hoists, cargo paternosters, etc., are erected within a specially constructed shaft in the building. The fire protection goal is to ensure that the products of combustion created during a fire are not allowed to enter the shaft. This is achieved by creating a positive pressure in the elevator shaft, and by installing diaphragms made of non-combustive materials at each floor level in the shaft service-line. If no diaphragms are installed, a positive pressure must be created there also. In the lower part of the shaft the positive pressure should be 20 Pa. Pressure in the upper shaft must be determined by engineering calculations influenced by local physical conditions. Obviously the walls of the elevator and service-line shafts should be constructed of noncombustible materials, and they should be airtight.
Horizontal conveyers should be provided with protective devices at the intersections with firewalls. These devices come in several versions. It may be a fire-operated valve which is normally kept open by a steel cable fitted with a fusible lock. Another version has a guillotine-type shutter closing the opening the conveyer passes through. It is kept in the open position with a fusible lock. One of these devices must be installed at each opening through which the conveyer passes throughout the building.
3.3.4 Requirements for laboratories and technical service rooms
The most dangerous pieces of equipment in terms of potential fire hazards are located in laboratories or technical service areas such as electrical and plumbing repair shops and the areas where the boilers and furnaces of central heating systems are located. These areas are subject to all of the fire protection procedures and standards previously listed, but specialized requirements may apply to certain pieces of equipment.
3.3.5 Fire prevention requirements for archives and library equipment
3.3.5.1 Storeroom equipment
The primary equipment located in storerooms is stationary or mobile shelving. All archives and library standards specify that only metal shelves shall be used, but in practice wood shelving also is used in some countries. The wood shelving obviously creates a constant fire hazard for those facilities that still use them. In some instances archivists and librarians have used fire retardant compositions on the wood shelving as an intermediate measure until they can replace them with metal shelving.
The practice of mounting records storage shelves on tracks is now appearing in new archives and libraries construction and renovations as an application of modern warehousing technology (compact storage). One aisle is provided for a series of shelving units, and, to gain access to a particular shelf, units are moved manually or by a motor until the aisle appears at the desired shelf unit. The use of compact shelving results in high fire load density that can lead to a fire that will threaten even the strongest code-prescribed fire barriers and construction, e.g., cause structural collapse. Without sprinkler protection for compact storage, fire endurance may exceed the resistance of fire compartment walls and the ability of the fire service to control it. Automatic sprinklers should be mandatory wherever compact shelving is used for libraries and archives.
However, it should also be pointed out that the potential for a total burnout of a records facility is exactly the same as for a similar amount of records on open shelving, except that for a fire to spread beyond control of a municipal fire department will take considerably longer with mobile shelving. Also, like records stored on open shelving, records stored on mobile shelving have the inherent capability to self-destruct and destroy the facility itself. However, slow spread of fire within the shelves, as occurs in mobile shelving, improves the chance of outside aid being effective.
Any additional equipment used in storerooms, such as bookcases, card catalog cabinets, etc. should also be made of metal. The introduction of any wood or other combustible material increases the fire hazards in a storeroom.
3.3.5.2 Office and reading room equipment
Public reading rooms are usually compartmentalized in a manner that separates them from the storerooms, laboratories, building technical support areas, and other areas. They are zoned through the use of fire walls and fire doors. Additionally, fire exits have been established and evacuation routes developed.
In addition to these precautions, archivists and librarians should deliberately lay out the research room furniture in a manner that enhances rather than impedes evacuation from the rooms. Just as the maximum number of people expected influenced the architect's design of corridors and passageways, officials should ensure that they have allowed sufficiently sized walkways through the furniture in the research rooms to permit speedy evacuation.
The furniture selected for the public research rooms should take fire safety into consideration. While metal furniture may not be considered appropriate for these rooms, drapes should be made of fire retardant material and materials used on chairs should meet established fire code standards.
3.3.5.3 Storage equipment in laboratories
The layout of laboratories must consider evacuation routes. It must also ensure that there is sufficient space provided around the area where staff works with potentially flammable materials to avoid any careless accidents.
Proper storage containers are essential in laboratories. Many chemicals used in the laboratories are flammable and some are explosive. These chemicals must be stored in special explosion-proof storage cabinets. In some instances chemicals must be refrigerated; in others, quantities of chemicals stored together in one storage cabinet should not exceed certain levels. Chemicals come with specific storage instructions which should be followed explicitly. As in other parts of the archives or library building, individual fire extinguishers should be placed conveniently throughout the laboratory. Laboratory application may require a different kind of extinguisher than is in general use throughout the building.