Probably one of the most overlooked areas during the spec-writing process for a new apparatus is the weight and mounting of portable equipment. After deciding on the purpose of the apparatus, it is essential to plan for the equipment needed to carry for that specific purpose.
Using NFPA 1901 will make it easier to plan the apparatus and the weight distribution of tools and other added equipment. The standard states that the support function of a vehicle represents the most concentrated and the heaviest load elements of the vehicle.
The design of what you carry on the apparatus should provide the following.
- Good load distribution
- Balance of the equipment (front to rear)
- Low center of gravity
When considering the layout, plan for fixed and loose equipment. Fixed equipment can be the generator, electrical and hydraulic reels, water tanks, compressors, and cascade systems. Loose equipment can be mounted forcible-entry tools, SCBA and spare bottles, and hand tools.
When planning the location of this equipment, consider existing equipment, proposed new equipment and, if there is unused space, what equipment may be load in the future.
The goal is to have a chassis with an adequate gross vehicle weight rating that is not overloaded. Meeting with the manufacturer’s engineers and having a list of all of this equipment beforehand is most beneficial in the design of your apparatus. Determining the cubic feet of space necessary to carry what you are proposing to place on the apparatus is another consideration.
This sounds like a lot of work, and it is. But, NFPA and the Fire Apparatus Manufacturers’ Association have resources to make it a little easier.
NFPA 1901’s Annex B has a document entitled Apparatus Purchasing Specification Form. This form provides a step-by-step guide to designing an apparatus and addresses many of the concerns buyers may have.
In addition if you visit the FAMA (http://www.fama.org) website you can download an Excel document titled Fire Apparatus Equipment Weight and Cube and calculator that lists every conceivable tool that you can carry, with its weight in pounds and measurements in cubic inches. Another document on this site is Emergency Vehicle Size and Weight Regulation Guideline — both are excellent resources for specing a new apparatus.
A new piece of apparatus should be an object of pride and something that will serve your community for years to come. Proper planning will ensure those objectives are met.