To access the remainder of this piece of premium content, you must be registered with Firehouse. Already have an account? Login
Register in seconds by connecting with your preferred Social Network.
Complete the registration form.
Cab-forward apparatus continued to be the predominant design until 1983, when Spartan Motors introduced the Gladiator chassis, which put the engine up front between the driver’s and officer’s seats. This design provided adequate cooling for high-horsepower diesel engines and opened up the entire rear cab area for multiple seating configurations. Shortly thereafter, Young Fire Equipment in Lancaster, NY, introduced the Crusader II mid-engine chassis. The first Young-built four-door, raised-roof cab was delivered to the Bailey’s Cross Roads Fire Company in Virginia on a 175-inch wheelbase with a clutch-controlled fire pump located under the cab floor. By removing the engine from the cab area, more space was available in the front for map books, computer terminals and other equipment.
While some in the apparatus industry did not believe these alternative engine designs would be popular in the tradition-bound fire service, within a few years other manufacturers were offering mid- and rear-engine chassis to increase crew-seating options. Most notably, Emergency One (now E-ONE) in 1985 introduced the Hush rear-engine chassis, which allowed seating for up to 10 personnel. These cabs were 94 to 96 inches wide with virtually no fender area to maximize the available space inside the crew seating area. For the first time, fire departments had the option to provide different seating arrangements and were not restricted to just four fixed seats.
At that time, engine and pump technology was introducing computer and electronic components that required chassis and cab space for mounting and maintenance access. Cab width had for the most part remained constant at 94 to 96 inches for years with minimal aesthetic exterior changes. Some departments operating with narrow fire station clearances recognized that while wider cabs provided improved crew space, they had difficulty maneuvering in tight locations.
NFPA 1901, in Section 14.1.9, provides guidance on minimum dimensions required for seating arrangements inside the cab. Each seating space must have a cushion at least 18 inches wide and 15 inches deep from the edge of the cushion to the vertical face of the seat back. In addition, each seating position must have a minimum of 22 inches of width at the shoulder level. These dimensions are being studied and validated based on a national anthropometric study of fire personnel conducted in cooperation with the National Fallen Firefighters Foundation (NFFF). The results of this several-year study will impact apparatus seating and seatbelt design, protective gear, step heights and many other aspects of our daily activities. Preliminary data from the study indicate the seat width to accommodate the 99th-percentile 2011 firefighter must be 28 inches. That is the width needed to accommodate a modern-day bunkered-up firefighter, and it is going to have a dramatic impact on cab design.
As a part of specification development, the apparatus committee should review department standard operating guidelines (SOGs), including staffing and assignments for each riding position. Just because you can specify a custom cab with seating for eight to 10 personnel is no reason to require this arrangement for your next apparatus unless your department can regularly staff it at this level. The number of seating positions on custom-chassis apparatus impacts a number of areas, including front axle, suspension and tire ratings, cab size and ultimately overall length.
Following are questions to answer before designing a cab:
• How many personnel normally will be assigned or will ride on this unit?
• What map books, computer and resource materials must be readily available for the officer?
• Where will protective gear be stored during non-emergency responses?
• What tools and equipment will be mounted and secured in the cab or an adjacent area?
Responses will provide insight as to what cab configuration will most benefit the department in terms of efficient use of space without compromising safety. Future articles will review current cab designs and discuss the importance of clear vision for the driver and officer seating positions, mounting of tools and equipment, stepping surfaces and other safety considerations.