Fire Engine



Background

The term "fire truck" is commonly used as a generic expression to describe a fire-fighting vehicle. Technically, a "fire truck" is a vehicle equipped with ladders and is used mainly to gain access to elevated portions of a structure or to provide a means of applying an elevated stream of water. "Fire engine" is a vehicle with a pump and is used primarily to pump water. A "fire wagon" carries large amounts of hose and is primarily used to lay hose as a complement to a pumper. "Fire apparatus" is the proper generic term for all of these vehicles. This entry will focus on the manufacture of a fire engine. From our first toys and books as toddlers to the everyday newscasts showing fire fighters in action, the fire apparatus remains one of the most familiar and impressive examples of technology in our lives. Uncontrolled fire was one of the greatest fears until quite recently. Early attempts to quell fires were merely bucket brigades, that is, lines of citizens handing water buckets to the fire, which was often ineffective against a fully involved building. Some attempts at increased water application were hand-operated piston pumps whose hoses pumped water from a holding tank or a pond. (These early hoses were made of leather with copper rivets; cotton hoses came into use in the 1800s.) Eventually wheels were added to the apparatus, but it was still pulled and operated by the firemen. Volunteer fire departments were established to man the equipment and fight the fire.

With the appearance of property insurance, insurance companies created fire departments and spent considerable time improving the fire apparatus. By the 1860s, the steam engine was used to operate the piston pump, and it was pulled to the fire by horses. Other attempts to pressurize the hoseline were chemical tanks, which used acid combined with soda dissolved in water to start a chemical reaction that would produce carbon dioxide. In this process, the carbon dioxide expanded, pressurizing the tank and propelling the entire mixture out of the hoseline and onto the fire. All of these designs were practically obsolete after the introduction of the centrifugal pump in early 1900. After the advance of the automobile, the internal combustion engine became the primary power source for the fire engine. Adaptation of the truck frame to accommodate the pump and tank completed the transition to the presentday fire truck apparatus.

Design

The basic design of the fire apparatus begins with a thorough review of the fire load and geographical terrain of the area the fire department will be responding to. The vehicle's ease of operation, adequate response speed, and equipment storage and deployment are all important factors to consider. The National Fire Protection Association (NFPA) has compiled guidelines for apparatus design based upon these and other variables. In addition, the fire fighters responsible for the apparatus also contribute to the design of the vehicle.

Most fire apparatuses are purchased by tax-supported governments, cities, towns, townships, and counties. In small departments, the design and approval process can take up to a year, mainly because of funding issues. When medium and large departments choose a new apparatus, funding is usually already established, and designs can be approved and purchased in less time. A fire engine can cost from $50,000 to over $750,000.

The basic fire apparatus has evolved into specialized units for particular types of fires and response. In the 1950s, pumpers, ladder trucks, and other miscellaneous designs such as small tankers and hose trucks were common, though airport crash trucks and large rural tanker trucks were also in use. Today, fire apparatuses are tailored to meet many kinds of specific hazards. Due to this wide variety, the rest of this article will discuss the manufacture of the basic combination pumper apparatus for small- and medium-size communities.

The Manufacturing
Process

The manufacture of a fire engine remains a custom, almost one-of-a-kind operation. Typically, a group of workers is assigned to the fabrication of the body and assembly of the truck frame. A separate group performs body finishing, then the apparatus is wired, equipped, and tested by a third, or "equipment," group. Aside from the body, manufacture of the fire apparatus is typically an assembly process.

This 1835 volunteer fire company's hose cart from Cleveland was decorated with sterling silver fitting to reflect their status. (From the collections of Henry Ford Museum & Greenfield Village)
This 1835 volunteer fire company's hose cart from Cleveland was decorated with sterling silver fitting to reflect their status.
(From the collections of Henry Ford Museum & Greenfield Village)

Fire was a plague in many early American cities. Americans responded with a variety of weapons: volunteer fire department's; inventions that prevented,, retarded., or fought fire; and insurance cooperatives ond plans that protected against losses caused by fire. Through the early and mid decades of the 1°fh century, a major fire was a calamity but also a social affair.

A city's volunteer fire companies often illustrated the city's social, ethnic, and demographic composition. Fire companies represented the ioyalty and corwaderies of special groups. Neighborhood pride, political rivalries, ethnic hostility, and class animosity were alt evident in the volunteer fire companies. Companies received public acclaim for their efforts and competed wiih one another for those public accolades. Af the first signal of a fire, companies would race to the scene pulling their hose carts and handpumped engines—not necessarily to catch the fire in its early stages. The commander of the first company to arrive would be in charge of the entire operation with absolute control over rival companies. Members fought with one another on the way and at the site, sometimes forgetting even to fight the fire! Once at the scene, more fighting could occur and volunteers were threatened as much by other firefighters as they were by the fire itself.

Members took great pride in their uniforms and equipment because these represented the group's social status as much as they did its fire-fighting competence. Equipment and uniforms were dtspfayed during public ceremonies and parades where competition for social status was particularly evident in pre-Civil War America. Hose carts and engine! were display pieces os well as functional equipment.

William S. Pretzer

Chassis

The basic design of the fire apporatus begins with a thorough review of the fire lood and geographicol terroin of the area the fire department will be responding to.
The basic design of the fire apporatus begins with a thorough review of the fire lood and geographicol terroin of the area the fire department will be responding to.

Body

Pump

Tank

Assembly

Painting

Installing wires

Quality Control

After the last accessories are installed and individually tested, the apparatus builder submits the finished truck to an independent inspection agency. The agency takes delivery of the truck equipped just as it would be placed into service. It operates and inspects all of the apparatus systems. The pump is operated at maximum capacity for two hours to assure that this vital component performs properly. Upon successful completion, the apparatus and the builder are awarded a certificate of performance. In many areas, the apparatus cannot be legally delivered without this certificate.

The Future

Many new technologies are being applied to the modern fire apparatus. New tank materials are increasing in strength while reducing weight, allowing for more water capacity. Some large departments are using computers and cellular communications to handle information about hazardous materials, structure design, and geographics of the fire district. Perhaups the most exciting of the new technologies in the fire apparatus is the increased use of Class A foam solutions to attack structure and vegetation fires. This involves a separate on-board foam concentrate tank and a mixing proportioner to combine the foam concentrate with the water in the proper amount. Class A foam coats burning surfaces and absorbs heat significantly better than water. When used with compressed air from a separate air compressor on the vehicle, this technology is known as a Compressed Air Foam System, or CAFS. The compressed air pushes the water/foam stream to a much greater distance, and the resulting foam clings like shaving cream. In addition to these advances, firefighters are becoming better trained and are customizing their equipment to fit the types of fires they encounter.

Where To Learn More

Books

Buff, Sheila. Fire Engines: Motorized Apparatus Since 1900. Longmeadow Press, 1994.

Fire Protection Handbook, 17th Ed., 1991. National Fire Protection Association, Quincy, Mass.

Periodicals

Cottet, Jack L. "Enclosed Cabs for Fire Apparatus." Fire Engineering, October 1990, p. 50-52.

"Agile Fire Engine Borrows from Racing Car Design." Engineering, September 1990.

Douglas E. Betts



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