Fire Protection and Prevention Chapter 11 Fire Protection and Prevention Fire protection includes procedures for preventing, detecting, and extinguishing fire. The procedures in these three areas of fire prevention aim to protect employees and property and to assure the continuity of a plant’s operations. To accomplish these goals, it is necessary to develop a plant wide fire protection program: FACILITY FIRE PROTECTION PROGRAM The primary purpose of such a program is to prevent fires from starting. a fire starts, employees should know their role in the following procedures: If, immediately detecting the fire and promptly transmitting an alarm initiating evacuation of the building confining the fire extinguishing the fire Objectives of a Fire Protection Program When planning a fire protection program, first make a statement of objectives for fire safety. When designing the plant’s building and laying out its operations, include greater measures of fire safety. Architects and engineers must realize that designing for fire protection is a legitimate part of their responsibilities. They must understand the special thermal load that fire puts on structural plans of buildings, and the preventive measures that can be included into their design. Some general facts about fire protection No facility is absolutely fireproof. Nearly everything can burn, by given ignition, adequate fuel, and sufficient Oxygen. Fire and flame will spread in a building both vertically and horizontally The spread of the heat, smoke, and toxic gases is possibly the greatest single danger to life and takes place in much the same manner as does the spread of fire. Smoke and toxic gases are responsible for 66% of deaths from fire in buildings. On-site early detection of a fire is absolutely essential. The use of a building—its occupancy—will influence the degree of fire hazards. The more hazardous the – materials handled in a plant area are, the more likely is the chance for a – fire to start and rapidly spread. The contents of a building are usually a more important factor in the start of a fire than the physical structure of the building. Very often only a few minutes pass between the beginning of combustion and the development of a destructive fire What happens, or does not happen, in the first few minutes of a fire determines whether it can be controlled or not. Fire Protection Engineering Fire protection engineering is a highly developed specialized field. The solution of many fire protection problems requires the special training and perspective of an experienced fire protection engineer. Achieving the most efficient fire protection system requires the involvement of the architect, interior designer, urban planner, building contractor, electrical and structural engineers, fire detection system manufacturers, building safety engineer, and local fire marshal. Fire Drills Fire drills, conducted at frequent intervals, demonstrate management’s concern and sincere interest in all fire prevention activities. The drills should serve as a reminder to employees and supervisors that all fire prevention practices are important. Prepare an emergency manual to outline procedures and drills and to assign responsibilities to each individual involved. Make prevention of personal injury and lost of life the main objective of emergency planning. Carefully plan and periodically carry out fire drills. Conduct them in a serious manner under rigid discipline. To eliminate panic in the event of an emergency and guarantee the smooth functioning of the emergency plan, carefully develop the plan. Post up to date instruction sheets, including evacuation routes, and distribute them to all employees. In addition, when going through fire drills, from time to time, block off an exit to see how employees would react to this situation in a real fire. Fire brigades Management cannot depend on automatic fire protection equipment, municipal fire departments to prevent fire losses. Fires can get out of control before municipal fire department arrives. One method of providing additional fire protection is to form a fire brigade. Brigade members should be regular plant employees from all departments, thoroughly trained in using the plant’s fire fighting equipment. Electricians, engineers, mechanics, and safety and fire inspectors all have special skills, thus making them valuable members of the plant’s emergency team. FIRE PREVENTION ACTIVITIES As a first step, all companies and plants should hold design review meetings for all new construction, as well as for changes in existing construction. Every establishment should institute procedures and regulations to assure that proper fire-extinguishing equipment is on hand and those employees are organized and trained to use the equipment correctly. Regularly schedule thorough inspections of all fire protection equipment. Keep a written record of these inspections. Fire prevention includes activities directed specifically toward preventing a fire from starting. Generally, these activities include inspections, fire drills, training fire brigades, and a good communication system. Inspections Set up a system of periodic fire inspections for every operation. Some buildings, operations, and processes require daily inspection, while others can be inspected weekly, monthly, or at other intervals. Buildings that are well designed and provided with protective devices and construction elements intended to act as fire safety features still need a periodic, detailed inspection program. In some establishments or plants, the safety and health committee locates and reports fire hazards. In large plants, this job is handled by a special subcommittee of the safety committee or by a person trained to manage fire risk. The inspector, fire chief, or other individual from the plant who is in charge of fire prevention and fire protection should establish inspection schedules, determine the direction-finding of reports, and have a complete list of all items to be inspected. Inspection of fire equipment should cover the following items: control valves on piping that supplies water for fire protection hydrants fire pumps hose houses and associated equipment sprinkler system water supplies including tanks automatic sprinkler systems special type of protection portable fire extinguishers fire doors, exits and aisles alarm and communication systems and routines communication to fire department Protecting Adjacent Buildings When a fire breaks out in a building, protect adjacent buildings by (1) closing every window facing the burning building. (2) stationing fire brigade workers with fire extinguishers or fire hoses at each window nearest the fire, and (3) stationing fire fighters on the exposed building’s roof with hose lines to keep the roof wetted down and with extinguishers to put out any burning embers. Training Employees Because extinguishers are effective only when fires are in their first stages, ensure that extinguishers are immediately reachable and promptly used by trained personnel. Extinguishers are only as good as the operators using them. Therefore, thoroughly train key workers on each shift. Fire extinguisher training is intended to teach employees how to stop small fires from spreading out of control. Use demonstrations to instruct employees in the use of extinguishers. At the demonstrations, simulate fire conditions. Have an instructor explain the fundamentals of fire fighting and the use of the equipment. Allow employees to get the ―feel‖ of the extinguisher in small organizations, have everyone in the plant attend and participate in the demonstrations. In large plants, train a suitable number of employees so that personnel trained in fire fighting are distributed throughout the plant. One of the most difficult decisions any employee faces is whether to fight a fire or to get out safely. If the following conditions are met, an employee might decide to fight a fire with an extinguisher: (1) there is a clear exit, (2) the fire brigade or department has already been called, (3) the fire is small, (4) the employee knows how to use the extinguisher, and (5) the extinguisher is in working order. An employee should-not fight a fire if (1) the fire is clearly spreading beyond its point of origin, (2) the fire could block the exit, or (3) the employee is unsure of how to use the extinguisher. Continue the training of employees with demonstrations, practice drills, and lectures at yearly interval or more often if a special fire hazard exists. Be sure that employees have printed instructions regarding the use of fire extinguishers. Communications Once a fire has been detected, especially in a potentially disastrous situation, good communications are necessary (1) as a means of alerting occupants to the emergency and (2) as a way to mobilize fire protection forces, whether a plant’s fire brigade, the municipal fire department, or both. A coded fire alarm system, with alarm boxes and bells, horns, or other sounding devices suitably situated, is usually needed. In very small plants, however, a steam whistle or similar device might be adequate. In any case, the alarm system is no better than employees’ training in how to respond when the alarm is sounded. In addition, install a backup-alarm system in-case electrical power is lost. Power is often lost during fires, especially if sabotage is involved: Also install a secondary power source, especially if electric pumps supplement the regular sprinkler system and standpipe system. Make sure that all persons can be alerted and that there is some way for everyone to get out of the building, regardless of the power source in use. FIRE DETECTION Statistical data shows that, despite good construction, cleanliness, and modern fire-fighting methods, a considerable number of losses from fire however occur. Losses would be reduced if each developing fire were detected so it could be attacked and extinguished. Thus, fire detection devices must be a part of every fire protection system. Means of detection could be a human observer; automatic sprinklers; smoke, flame, or heat detectors; or, more likely, a combination of these. The detecting part of a fire protection system has two main tasks: (1) Giving an early warning to enable building occupants to escape (2) Starting extinguishing procedures. Each automatic fire-detection system requires a sensor, which observes a physically measurable quantity of smoke, flame, or heat. Human Observer A human observer is a good fire-detection system for the following reason: He can take immediate action in a flexible way, whether calling the fire department or putting out a fire with an extinguisher. Be sure that employees report any fire that they have put out. Automatic Fire-Detection Systems In general, there are three possible errors in any non-human fire-detection system: (1) giving a false alarm, (2) not detecting a fire, (3) detecting it too late. The cause of false alarms may be human interference, mechanical or electrical faults, or special environmental effects. When planning an automatic fire-detection system, use the following checklist of questions: What is the main purpose of the system? What are the possible sources of ignition? What kinds of material will probably be ignited first? What kind of building construction is used? What are the environmental conditions? What kind of detection system has been installed and what are the reasons for choosing this system? How long can a fire be allowed to go undetected? There are many types of fire detectors to handle various situations and to detect various states of the beginning of a fire. Most manufacturers and distributors offer several or all of the commonly used types. • • • • • • Thermal Detectors Fixed-Temperature Detectors Line Thermal Detectors Smoke Detectors Flame Detectors Sensor Systems ALARM SYSTEMS Alarm systems can be divided into four groups: local, auxiliary, central station, and proprietary. All types of alarm systems should be equipped with a signal system that clearly communicates to all persons in the building, plant, or laboratory. Whenever an alarm is sounded in any portion of the building or area, all employees must know what the sound means. Local Alarm Systems A local alarm consists simply of bells, horns, lights, sirens, or other warning devices right in the building. Local alarms are generally used for life protection – that is, to evacuate everyone and thus limit injury or loss of life from the fire. A local alarm can be tied in with another system to call the fire department. Local alarm systems are inexpensive, available from a wide range of suppliers, and easy to install. Auxiliary Alarm Systems (supplementary) Auxiliary alarm systems are even less expensive than local alarm systems. Such a system simply ties a fire detector to a nearby fire call box. In effect, it becomes a transmit station triggered by fire detectors inside the building. Central Station Systems Central station systems are available in most major cities around the country. Operated by trained personnel, a central station continually monitors a number of establishments and, in case of an alarm, calls a nearby fire station and alerts the building’s personnel. Central station devices are almost always leased. Proprietary Alarm Systems Proprietary alarm systems feed alarms to the building’s maintenance force, and, optionally, to the fire department as well. One reason for their acceptance is that insurance regulations generally require security officers. Fires usually start in a facility’s contents or operations rather than in its structure. Therefore, consider the following: What materials are flammable? What materials in a process or operation are most likely to ignite? Burn? Explode? What in the facility could be a source of ignition? Are any open sparks or flames present? Are high temperatures involved in any operations? Where are flammable and combustible materials located? Are flammable materials stored together? Do indirect connections exist? If one of the materials should burn, could the others easily ignite? Might any of the materials ignite because of convection or radiation? What toxic gases might develop into a fire? How much time might it take for a fire to spread to other areas? to adjacent facilities? Smoke and toxic gases, and sometimes heat, are largely responsible for fire deaths. What toxic gases might develop from the burning of contents? How many people are likely to be involved in the facility, in adjacent facilities, or in facilities nearby? FIRE-SAFE BUILDING DESIGN AND SITE PLANNING The objective of fire safety is primarily to protect life and secondly property from the destruction of fire in a building. Building design and construction must take into account a wide range of fire safety features. Not only the interiors and contents of buildings are protected from the dangers of fire, but the building site it self must have adequate water supplies and easy accessibility by the fire department. Architects, builders, and owners may assume that state codes provide adequate measures; however, these codes specify only minimal measures for fire safety. Planning and construction based upon such codes may limit fire safe design seriously. Objectives of Fire Safety Design Before a building designer can make effective decisions relating to fire safety design, the specific function of the building and the general and unique conditions that are to be incorporated into it must be clearly identified. Decisions regarding the fire safety design and construction of the building have the same objectives as do all fire protection measures, namely (1) life safety, (2) continuity of operations, and (3) property protection. Life Safety Design considerations for life safety must address two major questions: (1) Who will use the building? (2) What will the people using the building do most of the time? Continuity of Operations Continuity of operations, the second major area of building design decision making, must take into consideration those specific functions conducted in a building that are very important to continued operation of the business and that can not be transferred to another location. Property Protection One of the most important questions to be asked about the design of buildings with regard to protection of property is: Is there any specific high-value content that will need special design protection? Materials of high value that are particularly vulnerable to fire and/or water damage can usually be identified in advance of building design. Fire Extinguisher How Does a Fire Work? Need all three components to start a fire Fire extinguishers remove one or more of the components Types of Fires Class A - fires occur in ordinary materials, such as wood, paper, cloth, carpets, and rubbish. Class B - fires occur in the vapor-air mixture over the surface of flammable liquids, such as gasoline, oil, grease, paints, and thinners. Class C - fires occur in or near energized electrical equipment Class D - fires occur in combustible metals such as magnesium, titanium, zirconium, lithium, potassium, and sodium. Different Kinds of Extinguishers The 4 most common fire extinguishers: All Purpose Water Carbon Dioxide Multi-Purpose Dry Chemical Dry Powder Each kind of extinguisher has a specific use All Purpose Water Use on CLASS A fires Pressurized water Pressure gauge Carbon Dioxide Use on CLASS B and CLASS C fires Hard, plastic nozzle Multi-Purpose Dry Chemical Use on CLASS A, CLASS B, and CLASS C fires Fine powder under pressure Pressure gauge Emergency Procedures Building Evacuation • Proceed to nearest exit in an orderly fashion • Assemble at least 100 feet from building • Provide emergency crews with information about people still in the building • Provide information to emergency crews about the reason for evacuation • Never re-enter a building until instructed to by the police department, fire department.