In the last installment of the Apparatus Architect we reviewed some history regarding fire truck cab design and the impact of staffing on seating positions and arrangements. Over the years with the advent of four door cab apparatus, more seating and equipment storage options have been developed by the manufactures to address the needs of the fire and emergency services. At a national level, studies are being conducted to validate criteria that were developed years ago regarding the anatomical characteristics of fire and emergency personnel. The results of this analysis will have a profound impact on future apparatus designs for seating positions, stepping surfaces, handrails and many other areas.
Today, many departments are operating with four to six personnel under the best of conditions. With this in mind several manufacturers are looking at how to maximize the available space inside of the cab for personnel, radio and computer equipment, protective gear, as well as other tools and equipment. Each of these areas needs to be carefully considered by the department to insure that you are meeting the objectives of the apparatus. Honest answers to the four questions raised in Part 52 of the Apparatus Architect will provide a solid basis for the design of you new unit.
One of the constant fire service complaints about current production cabs is the lack of room for the driver and officers seat positions. With the changes in engine emissions technology and electronics today’s diesel engines need more room for cooling and exhaust systems leaving little room for other critical chassis components. As most all custom fire chassis incorporate tilt cab, engine forward designs up until recently there was little that could be accomplished to improve the cramped working areas for the driver and officer.
Earlier in 2011, Pierce Manufacturing introduced the Dash CF cab and chassis to address many of the space, visibility, safety and maintenance issues by relocating the engine back towards the rear in between the crew seats and into the frame rails. This new cab design allows the driver and officers seat locations to be moved inward, improving the amount of leg, elbow and shoulder room. The Dash CF is 96 inches wide with an interior width of 92 inches, wall to wall.
When entering the cab the first thing you notice is that the first step into the cab is much lower to the ground, making egress into the cab much easier and comfortable. The two front steps are 18.50 inches from the ground with the height of the step to the cab floor being 16.50 inches. Inside of the driver’s door on the A post is long handrail which assists with entry into this area. The crew cab steps are only slightly higher and provide a non slip surface.
With the increased use of electronics, dashboard gauges and controls they are sometimes scattered in different locations across the width of the cab. In addition with radio and computer laptop mounting, the line of sight for the driver is limited when looking thru the windshield over to the officer’s side of the cab. Some departments have installed bumper guide posts and windshield mounted down view mirrors to allow the driver to view the right hand corner of the apparatus at the front bumper. The Pierce engineering team was able to lower the windshield some ten inches, providing almost unlimited vision for the driver when seated and belted, with no portion of the dashboard blocking the line of sight.
Safety measures some times come in small areas, such as location of dashboard instruments, emergency warning light controls, hazard indicators and other components. The Dash CF enjoys a logical arrangement of controls for the driver, particularly the position of the accelerator and brake pedals which have been problematic in some apparatus designs in the past.. The floor area between the driver and officer’s seats is open across the full width of the cab with the forward portion of the engine cover providing a logical mounting location for map books and other resource material.
With the engine located in the rear of the cab two seats are provided on each side, one forward and one rear facing, each equipped to hold self contained breathing apparatus. The engine box area measures 39 inches wide by 83 inches long and sits 23 inches above the level of the floor. The top, flat surface is a natural area to mount equipment such as hand lights, portable radios and irons. With a ceiling height of 61 inches in the front of the cab and 70 inches in the crew area there is adequate room for personnel to safely egress these areas.
There are more than several schools of thought regarding the amount of equipment storage that should be permitted inside of the cab area. For those very few departments that feel that they need more than six seating positions, the available space remaining inside of the crew area is very limited and by the time you mount a hand light and portable radio for each member there is no open area left for hand tools and equipment. This is where department SOG’s (standard operating guidelines) and training comes into play. Depending upon your staffing and response pattern’s, each seat on the apparatus should have a riding assignment to detail the specific job functions that each fire fighter is responsible for, including tools and equipment that each should carry and be responsible for at the scene of the incident.
The Pierce Dash CF provides more than sufficient room inside of the cab to carry those essential pieces of equipment that a battle ready fire fighter would have to have immediately upon exiting the cab. Safety is a mindset that all fire departments should strive to instill with their personnel when operating on apparatus and at the scene of any incident. The engineers at Pierce have a done a creditable job to assess many of the current problems with cab design and safety in addition to bringing about a reality check with respect to the size and overall length of a practical piece of fire apparatus.
With the cost of new apparatus, down time and maintenance costs becoming more of an issue, particularly where department’s do not have their own shops or repair facilities. Several maintenance friendly features incorporated into the Dash CF include a drop down panel on the officer’s side of the cab that permits access to electrical components, battery charges and windshield wiper motors. Fluid checks and fills for the engine and transmission are through a hinged access door at the left side crew cab door with chassis filters all located at one location outside of the frame rails. The chassis batteries are protected inside of the frame with ready access to the alternator and air cleaner.
With the number of innovations on the Pierce Dash CF chassis there will be some skeptics who are critical of the concepts and designs put forth with this unit. Many times we have heard the term to describe the fire service as “Two hundred years of tradition, unimpeded by progress”. Since the first steamer was introduced back in 1854 the fire service with few exceptions has been slow to universally accept new technology in many areas.
Consider that while metal, hydraulically raised aerial ladders were first developed during 1935, many departments continued to prefer wooden, spring raise aerial ladders which were built by several manufacturers up until 1955.
For many years the cab forward design was the predominate product available to the fire service. Departments across the United States used this type of custom cab to provide seating for four personnel and any additional members having to ride either on the back step or exposed in the jump seat area. Safety concerns, together with demographic changes in the inner cities created a new era of cab designs to provide enclosed seating areas for all personnel. These changes together with market driven innovations such as the Pierce Dash CF should provide a number of positive choices for fire departments to consider when specifying new apparatus for their fleets.
In future articles we will look at some recent success stories on how departments integrated safety and operational enhancements into their new engine apparatus. Who say’s that history does not repeat itself?
Photo captions for AA Part 53:
All photos by Tom W. Shand
1. The top of the engine box inside of the Dash CF cab allows space for tool and equipment mounting, here using Performance Advantage Company hardware to safely secure gear.
2. Engine and transmission fluid checks are accomplished thru this hinged door at the left side crew cab entrance. Note the color coded handles on each component.
3. The entrance to the driver’s compartment shows the full length handrail mounted on the door pillar. Note the location of the master battery power switch just below the dash board.
4. Controls for heater, defroster, air conditioning and other essential components are within easy reach of the driver’s position and do not block forward visibility.
Firehouse Magazine December 2011
By Tom W. Shand and Michael Wilbur