7 Guidelines to Determining Emergency Vehicle Reserves

November 2005, Government Fleet - Feature

by Dave Robertson

Reserve vehicles are often referred to by different names: extras, substitutes, spares, etc. Essentially, all of the labels fall under the term “pool.” That is exactly what they are - a collection of vehicles removed from front-line service to be re-used in an emergency or for some other utilitarian requirement.Most emergency fleet operators probably would welcome a formula to determine the correct number of spares needed to adequately support front-line vehicles or equipment. No such formula appears to exist. The following are some guidelines helpful when examining a fleet’s needs. A fleet manager should apply not only qualitative thought processes, but also quantitative analysis to support actions and recommendations. Meaningful data is critical to establishing needs. Police and fire agencies sometimes attempt to support requests and recommendations based on the statement, “We are a life safety department.” That argument usually is not effective.Consider Options
To determine adequate reserves, several considerations must be addressed. These factors will provide better insight into the most efficient use of agency vehicle assets and help justify final decisions. Some of these considerations will weigh heavier than others in particular fleets. The first consideration is area of coverage or how front-line units are dispersed or deployed. Geography may dictate the number of reserve units. County or metropolitan agencies that span vast areas may require additional reserve units to cover longer distances. In this case, dispersing reserve units for better coverage might be a solution. Therefore, a centralized pool of reserve units may not meet operational needs for time and distance to quickly obtain a reserve.A second consideration concerns front-line fleet usage. Generally, higher utilization of front-line vehicles - with their accompanying breakdowns and accidents - indicates a greater need for reserve units. In the fire service, utilization is often measured in “runs” and not miles. In fact, most fire service vehicles may have little mileage. In large cities, a long run might be only two miles, but the unit may stay operating at a fire scene for hours. Similarly, police patrol vehicles in large cities may not incur high mileage, but they may run high idle times, increasing vehicle wear. Ford is adding hour meters to its patrol car specifications due to the increased recognition that idle-time hours diminish the life of the vehicle. Without this measurement, usage could be significantly understated.{+PAGEBREAK+} Manage Utilization
Emergency service personnel often want to use a familiar unit on the job. This is especially true with some police agencies. Such reluctance to rotate vehicles can significantly increase vehicle utilization operated every day. Some police agencies are also reluctant to change assigned vehicles. For instance, particular vehicles may be set aside for use by sergeant-level personnel. Or one car may be assigned among three patrol shifts, ensuring 24 hour-a-day utilization. Front-line vehicle utilization must be managed to ensure that vehicle wear is relatively equalized.A third consideration is age and condition of the front-line fleet. When everyday units are in poor condition, demands placed on reserve units increase and the need for additional units grows. Accidents affect front-line unit condition. Reserves based solely on accident history, however, is a difficult justification. Forecasting a number of reserves based on an accident rate expectation is tricky.Police and fire services (including ambulance service) require a dependable replacement plan to help manage the size of the reserve fleet. Typically, these fleets require a greater number of reserve units to support front-line vehicles. Therefore, an adequately-planned reserve fleet is based on the ability to replace vehicles in a timely and predictable fashion.Reserve Unit Condition a Factor
A fourth consideration in a reserve fleet formula is the condition of the reserve fleet. Obviously, a reserve fleet comprised of units in poor condition will require additional units. A fleet manager will generally retain the best units once those units are removed from front-line service. The number of reserves required will depend on how well the units were maintained and repaired while on the front line.The fifth consideration is the usage of the reserve fleet itself. Utilization is often the most important factor in determining a reserve fleet size. Constant use of the reserve units indicates front-line units are not being replaced, many times the result of deferred funding for new units. Keep in mind that the reserve fleet plays other roles in addition to serving as front-line replacements for units sidelined by maintenance, repair, and accidents. Reserve units are used for special events, such as parades, sporting events, other large public or political gatherings, or Homeland Security issues. Certain special police operations require the use of overtime units to provide additional police presence. These vehicles are drawn from the reserve fleet.Outside Recommendations
Industry recommendations are still another consideration in determining reserve fleet size. The National Fire Protection Association (NFPA) recommends that fire service agency have one spare or reserve engine for every eight engine companies. The same recommendation applies to aerial devices. A fire agency with less than eight engine or ladder companies will require at least one spare. The NFPA can only suggest recommendations. The decision on an appropriate number of reserve units rests with the fleet manager and the head of the fire agency. As an independent reference, the NFPA recommendation is a valuable standard to support the reserve fleet size when questioned by elected officials or concerned citizens.Finally, a seventh consideration is the 10-percent rule, a measure often cited in planning a reserve fleet. While a common benchmark, it is a working number only, supported by little hard evidence. Apply this rule if it works for your fleet after thorough analysis. In the end, policy may be the determining factor in reserve fleet size. The fire or police chief may simply dictate how many reserves and/or extra units are required. The fleet manager has an obligation to confer with agency chiefs to work within the policy. In summary, there is no “one-size-fits-all” or correct number to use in sizing a reserve fleet. Apply the considerations mentioned above, with appropriate data, to obtain a reasonable estimate for the number of reserves required. Based on the process, the justifications for deployed or required assets will make budgetary sense.

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