This is a brief paper on fire safety in buildings and structures, with some aspects on fire engineering, and prevention. Fire safety in buildings and structures initially involves careful engineering that requires scientific study for engineering application.
There are laws, or codes, that should be followed on designs and engineering of buildings and structures. The use of a fire safety engineering approach provides a more precise design necessary for the assessment of new and complex projects.
However, laws or codes on fire safety and engineering are sometimes perceived as inflexible, and also seen as prescriptive regulations: some are seen as inadequate to meet the challenges of new materials and innovative design.
Fire safety encompasses fire prevention and other fire safety engineering methods, and topics on materials and equipment for safety and prevention. Fire prevention is everyone’s concern, but huge responsibility lies in the fire chief who is forced to deal with emergency incidents involving buildings and structures (Diamantes, p. 84).
Codes on fire prevention and safety have been instituted since the early 20th century. These were applied to contain fires not only to a building, but also eventually within a building. Limiting fire spread from building to building is accomplished through several means: restrictions on area/height of a building, limits on the combustibility of roofs and exterior wall surfaces, minimum separation distances between buildings, limits on openings in exterior walls (doors and windows), and fire-resistive exterior walls (Brannigan, p. 80).
Preventing fires means reducing fire losses. Total fire costs include not only direct fire damage but also the costs of preventing and controlling fires. While the cost of fire losses has continued to rise, the number of deaths from fire has, fortunately, declined slightly (Schroll, p. 1).
Fire Safety Engineering
Architects and engineers should have adequate knowledge of fire in its key stages like ignition, fire growth and other combustion aspects in order to incorporate this knowledge in their design or architectural processes of the building. Fire safety in buildings and structures initially involves careful engineering which requires accuracy and scientific study.
Safety engineering is “the provision of adequate fire safety precautions in a complex building or structure that accommodates a departure from the prescribed performances in any specific area by taking other higher or compensatory measures in another area” (Christian, p. 3).
The concepts of fire safety engineering may be applied to any situation where fire is a potential hazard (Purkiss, p. 1).
The International Organisation for Standardisation (ISO) has produced a comprehensive Technical Report that has now been published by BSI as BS ISO/TR 13387, fire safety engineering. (Christian, p. 4).
Causes of fires
Causes of fires are attributed to poor building design, inadequate emergency procedures, and lack of protective devices like automatic sprinklers. Aside from the building design, fires are exacerbated by combustible interior furnishings (Clinton, p. 8).
A fire detection alarm is needed in fire safety engineering in order to prevent further damage caused by the fire, or to warn the owner, or authorities such as the fire department, and the general public. Early detection can lead to early suppression of the fire and prevent it from spreading before it could cost much damage to the building or structure.
Fire-fighting devices initiated either manually or by the fire detection system are installed in buildings and other structures. Such automatic devices vary depending on the type of fire to be expected but they generally operate by smothering the fire and denying the fire any source of oxygen.
One of the devices that reduce temperature of burning materials is the sprinklers. Sprinklers effectively act by reducing the temperature of the burning contents. Any fire-fighting system installed as part of the fabric of the structure should be supplemented by the supply of both suitable portable fire extinguishers and by hose reels for local fire fighting. The value of installing an automatic sprinkler system for life safety and property protection has been well documented over many years of service in a variety of specific applications. The sprinkler system should also be maintained in such a condition that it is always ready to discharge water on a hostile fire (Leber, p. 43).
Hydraulically Operated Water flow Alarms
Hydraulically operated water flow alarms are also called “water motor gongs”, which operate very much like a miniature version of the water wheel that operate the mill shafting of a textile mill. When an automatic sprinkler fuses in a fire, when a pipe breaks, or when a fitting develops a significant leak, water is diverted through an open alarm control valve to a nozzle assembly that directs a stream of water against the paddles of a water wheel. Then when the wheel turns, it operates a striking mechanism that repeatedly strikes the shell of a large gong, which then produces a loud clanging sound that can be heard in the vicinity of the sprinkler riser (Leber, p. 44).
The fire alarm system should monitor all fire alarm initiating devices. Examples are manual fire alarm boxes: heat, smoke, radiant energy, fire-gas, or other fire detection devices; and the discharge of automatic sprinkler systems and other fire suppression or extinguishing systems, such as dry chemical, foam, foam-water, water mist, carbon dioxide, and other gaseous agents. Early detection of fire can contain fire.
As time goes by, improvement in the understanding of fire and its behavior enables designers to better design fire alarm systems to achieve specific objectives and levels of performance. System reliability should be maintained as high as possible. Reliability is essential for fire alarm systems.
According to Cholin (55), the highest objective is life safety, and the second is mitigation of property damage through the timely actuation of automatic fire extinguishing systems and transmission of fire alarm signals to the fire service.
The concept and practice of fire prevention has been observed in recorded history, although two hundred years ago, this was still a very new phenomenon. When we talk of fire prevention, there are many correlated terms used, examples are fire-rate, fire-proof, flameproof, and so forth. A planner or anyone involved in fire prevention and safety should take note and look for the real meaning of these terms because they are sometimes misleading to the public. For example, the term inflammable has been found to be misleading and there are efforts to eliminate it from fire protection literature.
Fire science is a growing subject in fire prevention and safety. Architects and engineers have to study it in their fire prevention applications.
Fire safety in buildings and structures initially involves careful engineering which requires accuracy and scientific study for engineering application; this is aided with experience and judgement, as in other engineering disciplines. Engineering involves the need to evaluate fire hazard and risk and to offer fire safety strategies and designs based on performance not prescription. Safety engineering is much needed in fire safety because engineering is a discipline that involves careful planning.
Incorporating safety measures in structures and buildings should have a careful study by the engineer or architects, and the codes regulating this planning should be flexible enough to give more lee-way for the engineer doing the planning. The principles in the code must enable the engineer to properly plant the fire safety framework.
Experience tells us that the causes of fires are due to poor building design, inadequate emergency procedures, and other necessary measures not being implemented, such as automatic sprinklers. Furthermore, interior furnishings exacerbate the growth of fires, or they could be the primary cause of fire. Materials are combustible. Engineers and architects should not neglect installing the necessary fire protective devices in buildings and structures. In hotels and buildings for public use, owners should be extra careful in installing combustible materials which are said to be “fuel load” to possible fires.
Moreover, fire detection alarms are a necessity in buildings and structures to warn occupants of an existing fire. Computerized fire-detection alarms are now available at reasonable prices. These alarms are applied with the necessary IT tool or software which can aid the engineer or designer in planning the fire-safety measures in buildings.
Nowadays, high-rise buildings and structures use sophisticated fire detection alarms to warn occupants and maintenance crews of an existing fire. There is also the surge of sophisticated smoke detectors to increase fire-detection methods. The addressable fire alarm system is both automatic and manual operated. The photoelectric smoke detector is composed of a sensitive electronic circuit that provides alarm in case smoke is detected. Photoelectric detectors can be installed in high-ceiling areas and spaces with medium to high-velocity airflow at the ceiling level. The air-sampling detection system uses a laser beam-based photoelectric smoke detection. Warning and protective devices are also installed in air-conditioning units which may add “fuel load” to an existing fire.
In the study of fire prevention, it is always important to consider the preparation and the planning of the various needs in preventing fire. Fire can become predictable if fire safety engineering is coupled with scientific application and the right formulas instituted like in many other disciplines.
The essential objectives of a fire alarm system, which are safety of lives of occupants of a building, property protection, and continuity of the site’s mission, can be achieved in the event of a fire only if the alarm system functions properly. The proper maintenance and reliability of fire alarm systems should be instituted by the building owner or other persons or authorities concerned. The system elements, like design, equipment, installation, and maintenance, are very critical to the reliability of the system.
Experience and more studies and researches on fire behavior and its causes can help us reduce fire incidents and fire losses.
- Brannigan, Francis L. Brannigan’s Building Construction for the Fire Service (Fourth Edition). London: Jones and Barlett Publishers International, 2008. Print.
- Cholin, John M. “Fire Alarm Systems: Inspection, Testing, and Maintenance.” Operation of Fire Protection Systems. Ed. A. Cote. Massachusetts: National Fire Protection Association, Inc., 2003. 55-74. Print.
- Christian, Dr S D. A Guide to Fire Safety Engineering. Essex: British Standards Edition, 2003. Print.
- Leber, Fred. “Fire Alarm System Interfaces.” Operation of Fire Protection Systems. Ed. A. Cote. Massachusetts: National Fire Protection Association, Inc., 2003. 43-52. Print.
- Purkiss, John A. Fire Safety Engineering: Design of Structures (2nd Edition). UK: Butterworth-Heinemann, 2007. Print.
- Schroll, R. Craig. Industrial Fire Protection (2nd Ed.). United States of America: CRC Press LLC, 2002. Print.