Industrial Fire Protection and Prevention
IN THE LAST TWO DECADES, considerable advancement has been made in fire protection for industrial plants. However, there is still ample room for improvement in the educational and practical aspects. Modern industry continues to develop new processes which challenge those devoted to the field of fire protection engineering. It is only through dedicated research and development that new hazards can be controlled or eliminated.
When planning new plant construction or major alterations and additions, architects and engineering personnel should be apprised of the requirements to make the property as safe from fire as good practice may dictate. Budget-wise, operators must evaluate their respective hazards and the calculated risk potential. Some authorities establish percentage allocations of funds in relation to the total engineering estimates of new construction and major alterations. Monies set aside for safety and fire protection design and equipment may range anywhere from 1 1/2 per cent for light-hazard occupancies to as much as 7 per cent in the petrochemical field. On the other hand, an engineering estimate involving alterations may exceed these figures by 50 to 75 per cent because of difficulties encountered in the designs required for existing structures.
Once the plant is in operation, the fire protection funds must be derived from the annual operating budget. Here again, the amount allocated should depend upon the values at risk. Usually the total assigned is far less than required since there is no apparent return on the expenditure. However, sprinkler systems, water supply and fire fighting equipment function only as effectively as they are maintained and handled. Training of fire brigades, preventive maintenance of the previously mentioned equipment and overhaul of various types of production equipment necessary for the protection of life and property are musts. Usually five-tenths of one per cent per year should be adequate to carry out such measures. In some instances, plants with hazardous areas may require more frequent replacement of certain equipment due to use or corrosion. These installations may have as much as 1 ½ per cent of their budget assigned to fire protection or life safety of their employees.
Photo by Rudy Moc Studio—courtesy Alan Smythe, vice president, the Thew Shovel Co., Lorain, Ohio
The planning stage
The planning stage should incorporate a survey of the site to ascertain: (1) Available water supply (public or private) in sufficient quantity to cope with occupancy hazard; (2) topography of the area (this is particularly necessary for location of certain processes and storage areas of flammable liquids and gases);
(3) adequacy of municipal fire fighting forces available within a 3-mile limit;
(4) approaches to the building site for access by apparatus under adverse weather conditions.
The technique of reviewing plans of new construction or remodeling has become an effective means for planning fire protection prior to actual construction. The value of so-called “engineering plan review” has met with such success that a number of state agencies throughout the country have integrated this procedure in their industrial health and safety programs. A technical conference between the fire protection engineer, the architect and management brings out the necessity for physical separation of hazardous from nonhazardous operations in the plant, requirements with respect to safe handling of processes in flow and in storage, as well as adequate egress features for life safety.
Furthermore, such conferences determine compliance with the basic provisions of existing codes and good fire protection engineering practice. In many instances, no set rule or standard may exist and technical background assistance will be needed to determine the extent of the requirements for the particular plant. However, it must be kept in mind that codes are the “minimum requirements” and are not necessarily the most desirable preventive measures for an installation. Such rules should be used as a fundamental basis upon which to build your processes and structures.
In modern design, lightweight web or bar truss roof members are widely used. Unless adequate protection is provided, fire will make short work of such a structure. Enclosure of the entire member in a skirt of metal lath and 1 1/2 inches of vermiculite and gypsum plaster will offer a good two hours of protection. Steel “H” or “I” beams may be placed in a manner to permit a precast roof to use the lower flange for support in one-story buildings, thereby only exposing the surface of the lower flange to the fire potential. In warehouses or storage areas where fire may develop high calorific heat values, it is most important that proper protection be given the steel members of the building.
Where wooden trusses or roof members are used, a wood preservative impregnation may lengthen the failure time, thus giving resistance to fire superior to untreated wood. Research has made much progress of recent years in the application of fire-retardant coatings which reduce the spread of fire.
Where masonry walls are of less than brick or reinforced concrete in construction, they should be scarfed into the columns. In the case of concrete block, it is preferable that the column lie a brick pilaster with scarfing arms at least every fourth block depending upon design loads. Although somewhat more costly than conventional column design, it gives considerable more rigidity and strength to the structure.
Architectural trends today lean toward windowless walls, primarily because of the wide use of air conditioning. When such structures are contemplated, the designer should review fire fighting tactics and visualize how a fire can be suppressed without adequate access by the fire department. With the installation of removable bubbles or skylights, or those actuated by a spring-loaded, fusible mechanism, adequate ventilation of hot gases may be possible. However, access by hose lines must still be made available. This may be accomplished by locating soft spots of 4-inch tile or concrete block at strategic locations. Such “knock-out panels” can be identified by means of a rosette, medallion or other suitable means of identification. The municipal fire department, when advised of such panels, will have an immediate access for normal fire fighting tactics.
With total air conditioning, additional hazards are added to the complex problems of design. Duct work may carry hot gases and flame to remote areas in a building unless adequate cut-offs are provided by fusible dampers (see NBFU Pamphlet No. 90-A). Duct work is usually installed in the void created by a hung ceiling. This can cause serious delays to fire attack in such areas. It is of extreme importance that such voids be constructed of noncombustible materials.
Management should establish a method of period inspections whereby the entire property is subjected to a fire prevention inspection. Fire causes are well known through carefully recorded statistics during the past years. Most fires start with conditions which may be easily recognized not only by the fire protection engineer, but also by the conscientious management staff. Most fires, therefore, may be prevented by the simple process of correcting such conditions.
Suggested Inspection Check List
Results of self-inspection reports should be reviewed at the monthly safety committee meeting. The committee should be made up of management, engineering, development, plant maintenance and operational personnel. Their duties are to review all accidents, discuss new processes, iron out defects in present operational processes and bring to the attention of the “front office” any condition which might result in “downtime” for the plant or any department.
A particularly desirable result of such committee functions is the review of conditions based upon the unfortunate experiences of others. Such experiences, well analyzed, can act as a guide to help eliminate or alleviate hazardous conditions in the plant.
In addition to electrical faults and allied hazards, there are three “gremlins” which under certain conditions create serious fire potentials in a plant. These are flammable liquids; welding, brazing and cutting operations; and poorly planned processing.
Flammable liquids must be stored and used with due caution. Movement of such materials create electrostatic charges which may ignite vapors present whenever such liquids are in use or in storage. Electrical equipment, unless installed according to code, exposes a plant to explosion potentials where volatile liquids and vapors are present.
Regardless of the type of plant, whether engaged in the use or manufacture of a hazardous material or a plant handling products normally assumed to be nonhazardous, the seriousness of operations involving the use of welding equipment has been greatly underestimated. Such equipment should be used with extreme care, making certain that protection is afforded combustibles and flammables by means of segregation, ventilation, use of flame-retardant curtains and shields. Above all, when such equipment is shut down, a continuous fire watch should be maintained for at least an hour. The affected area may be subject to ignition for that period of time.
Certain processes in themselves create a fire hazard due to any number of causes. Machine bearings become overheated; flammable vapors emit from certain materials; drying ovens may overheat products in process; dusts may be created and many other faults may develop. It is only through thorough study and careful planning that a fire potential may be avoided.
Explosion hazard
An explosion is “the sudden and violent increase of pressure.” This may take place through a rapid chemical reaction or sudden release of gases or vapors under pressure. The latter is of a physical nature as exhibited by the rupture of an air tank or boiler. Where chemicals of a volatile type are involved, fire is certain to follow. A good many industrial plants have suffered severe losses from explosion where such a hazard was unsuspected. A review of all plant operations and equipment by competent personnel should be considered to prevent the development of an explosion.
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INDUSTRIAL FIRE PROTECTION
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Explosions may be prevented by (1) proper plant design, (2) an effective preventive maintenance program, (3) well-planned operations in the flow-sheet stage and (4) competent and welltrained personnel. Management can obtain technical help in this area through the U. S. Bureau of Mines, the American Society of Mechanical Engineers, the Manufacturing Chemists’ Association and cooperation with their own fire insurance engineers.
Cooperation with outside agencies
When an inspection by a competent fire protection engineer indicates the need for changes in operational procedure or structural design, management should take action. Complete surveys by the engineering department of the Factory Insurance Association, Factory Mutual Engineering Division of the Associated Mutual Companies, National Board of Fire Underwriters, or competent consultants in this field are a basic foundation upon which to build a fire-safe plant. Such groups are experts in their field and can offer assistance found nowhere else in the engineering profession.
Liaison with fire department
Plant managers should make every effort to maintain friendly relations with the fire fighting forces of their municipality. Through courtesy visits to the local fire station and by invitation to the fire marshal or chief to “come see what we make,” a common ground for discussion of fire problems can be made.
It is of vital importance that fire department personnel have previous opportunity to become acquainted with the plant. Members of the first-due engine companies must be familiar with the general layout of the plant for ingress purposes, and points of high hazard.
In plants where hazardous materials are handled or processed, a key member of the staff should be assigned to work with fire department inspection teams in order that a multiple-hazard condition may be avoided.
In connection with this cooperative project, the man assigned should be present at pre-fire planning drills in order that the members of the fire companies responding can avail themselves of local operational “do’s and don’ts.” In addition, the plant liaison officer will know the type of approach tactics the fire department will make in certain areas of his plant.
Evacuation
One of the basic functions of any wellplanned fire protection program is the safety of personnel. Fire is still the initial cause of panic which has taken many lives. No hazard, including explosion, should be overlooked in the preparation of an evacuation or emergency exit plan.
The number of exits, their capacity according to code, location, alternate means of egress and a thorough knowledge of the plant operations including exceptional hazards are phases of planning which will require considerable thought. Enclosed stairways are preferable to outdoor escapes and ladders, as weather conditions may make fire escapes extremely hazardous to use.
Group leaders should be chosen to act as guides in case of evacuation. Instructions to these leaders should cover in detail precisely what alarms will be given and the egress stairway and alternates to be used. Drills should be varied so that all means of escape are used at one time or another. Thorough planning and proper supervision are absolute necessities in emergency egress evolutions.
Fire brigades
Employees in plants or other areas where three or more persons are on the premises should be trained in fire fighting. Normally, when one speaks of a fire brigade, 10 to 15 or more men are visualized. Such a crew may be satisfactory where 35 to 50 employees are on a shift, but what about the small plant where only two or three men are operating automatic equipment? The answer is, train all employees in the fundamentals of panic prevention, evacuation, chemistry of fire, and fire fighting with firstaid fire appliances such as extinguishers and standpipe and hose lines.
For the small plant of five to 15 employees on a shift, a limited fire brigade unit of three to five men should be established and additional units provided as required. Training of these men would consist of an intensive course in the suppression of fires utilizing the various pieces of equipment found on the premises. A suggested curriculum would be:
Ropes, knots and hitches
Hose
- Care of hose
- Care of couplings and gaskets
- Care of nozzles and play pipes
- Hose evolutions
Ladders
- Care of ladders
- Hook or roof ladder
- Wall ladder
Gas masks
- Canister type
- Care and maintenance
- Uses
- Limitations
- Self-contained masks
- Care and maintenance
- Uses
- Limitations
First aid and resuscitation
- Definition and purpose
- Dangers of limited knowledge
- Treatment of cuts
- Treatment of shocks
- Use and care of inhalator
- Rescue methods
Salvage
- Reasons for practicing salvage
- Care of covers
- Knowledge of sprinklers
Miscellaneous subjects
- Tactics
- Ventilation and attack
- Hydraulics, pumps, care and operation
- Inspections
- Chemistry of fire
- Automatic sprinklers
- Exposures
- Fire prevention
- Safeguarding hazards
Municipal drillmasters and state fire marshals often include industrial brigade training with their routine classes. Employees trained in the techniques used by municipal firemen places another team on the side of the fire fighting forces.
In organization, there should be fire companies headed by chiefs, captains and lieutenants as in the municipal service. In an advisory capacity, certain key personnel should be an integral part of the plant fire brigade, particularly where hazardous chemicals or processes may be encountered. A typical organizational chart for a chemical plant is shown.
In order to have a fire-safe plant, it is necessary to develop a 24-hour program of prevention and protection all the way from the executive officers down to the janitor. In these days of uncertainty, it is well to plan for eventualities beyond normal anticipation and cooperation with local officers of civil defense should be sought. Definite plans may then be developed for either man-made or natural disasters. Planning should include mutual aid and assistance to neighboring industrial plants, should the occasion arise. When disaster occurs, panic may follow but preplanning and adequately trained personnel will reduce this hazard to a minimum.
BIBLIOGRAPHY
Shepperd, “Fire Chief’s Handbook.” Business Papers Division, Reuben H. Donnelley Corp., New York
Associated Factory Mutual Fire Insurance Companies, Norwood, Mass., “Organizing Your Plant for Fire Safety”; Approved Equipment for Industrial Fire Protection”
National Fire Protection Association, Boston, Mass., “Vols. 1-6, National Fire Codes— 1958”
Manufacturing Chemists Association, Washington, D. C., “Safety in Chemical Laboratory”
Sax, “Dangerous Properties of Industrial Materials,” 1957, Reinhold Publishing Co., New York
Pieters, “Safety in Chemical Laboratory,” 1951, Butterworth Scientific Publications, London
Cameron, “Chemistry in Relation to Fire Risk and Fire Extinction,” 1948, Sir Isaac Pitman & Sons, London
National Board of Fire Underwriters, New York, “Special Interest Bulletins”; “Building Code”; “Fire Protection Through Building Codes”
National Safety Council, Chicago, Ill., “Safe Practice Pamphlets”
