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A red and white Pierce fire truck sitting on a winding pavement road with mountains and trees in the background.

Elevation can significantly impact the performance of a fire truck's pump due to changes in air pressure and density.

To help clarify common questions and aid fire department representatives as they consider adding a new pumper apparatus to existing fleets, we asked the Pierce Manufacturing pump engineering team to walk through the effect of elevation on pump performance.

Does Elevation Impact Fire Truck Pump Performance?

A red fire truck, with a '21' on the grill, driving down a hilly winding road, with a mountain on the side.As fire trucks operate at higher altitudes, several key factors impact water pump efficiency, performance and operational capacity.

1. Reduced Air Density Leads to Decreased Pump Efficiency

At elevations above 2,000 feet, air density decreases. This thinner air contains less oxygen, which is crucial for the combustion engines powering pumps on fire trucks.

Fire truck pumps function by creating a pressure differential, which helps move water through the system. However, at higher altitudes, the reduced atmospheric pressure lowers the maximum pressure differential achievable by the pump. This limitation restricts the pump’s ability to effectively move water, which can affect firefighting operations, relying on consistent and powerful water flow.

2. Increased Cavitation Risk

Another significant issue at high elevations is the increased risk of cavitation within the pump. Cavitation occurs when the pressure inside the pump falls below the water's vapor pressure, forming bubbles. When these bubbles pop, it creates turbulence, which can cause severe damage inside the pump. The damage primarily occurs to the impeller typically made of brass. The turbulence from cavitation degrades the leading edge of the impeller, diminishing its effectiveness and leading to increased wear and tear. This degradation not only reduces the pump's efficiency but also its lifespan, requiring more frequent maintenance or the replacement of key components.

Fire departments operating at higher elevations may need to adjust their equipment and tactics to account for these changes in pump performance. Or they can work with Pierce Manufacturing to source and size a pump specifically designed for high-altitude operation.

How Are Pierce Pumper Apparatus Designed to Address High Elevation Impacts?

A red fire truck on a flat pavement road with snow capped mountains in the background, with a blue sky.When fire departments operate in areas of high elevation, the performance of the fire truck’s water pump is crucial.

Understanding this, Pierce Manufacturing takes proactive steps to ensure each pumper apparatus is specifically designed to address the impacts of high elevation on overall operational effectiveness, detailed below.

  • Early collaboration. Pierce collaborates closely with water pump Original Equipment Manufacturer’s (OEM) to source and size pumps for the unique characteristics of the community where the fire truck will serve.
  • Detailed communication. During the procurement process for each water pump, Pierce provides the OEMs with detailed information about the elevation where the fire truck will be used. This data is critical because it allows the OEMs to tailor the pump, particularly the impeller, to perform optimally at high elevations.
  • Tailored design. The pump customization process focuses on modifying the impeller design to compensate for the thinner air and lower atmospheric pressure found at higher altitudes. This tailored approach is crucial when the pump operates at the high end of its rated capacity.
  • Tested for proven performance. During the UL fire truck certification and inspection process, Pierce simulates elevation to test pump performance and verify maximum output.

Pierce includes elevation-based pump customization as a standard part of the procurement and build process for every custom fire truck order.  

Elevation-based pump customization as standard practice ensures when a Pierce pumper apparatus arrives at a fire department, it is already equipped to meet the challenges of its new environment, providing reliable performance and enhanced firefighting capabilities.

This proactive approach optimizes the pump's functionality, extends its lifespan and reduces the need for frequent maintenance, even under the strenuous conditions posed by high-altitude operations.

A red and neon yellow striped back end of a white and blue fire truck driving down a hill on the side of a mountain.

What Can Fire Departments Do To Maintain Pump Performance?

Maintaining the performance of fire truck pumps is crucial for effective firefighting operations, especially in challenging high-elevation environments.

Here’s how fire departments can maintain and even enhance pump performance through strategic planning and regular maintenance.

1. Strategic Specification of Pumps

When specifying a new fire truck, it is important for departments to consider not only their immediate needs but also the longevity and reliability of equipment under various operational conditions. 

Understand how often the water pump will be used and at what capacity. For example, some departments opt for a higher gallon per minute (GPM) rating than necessary. This extends the life of the water pump by operating it well within its capacity, reducing wear and tear.

2. Annual Certification and Testing

According to NFPA 1900 Standard for Automotive Fire Apparatus, fire departments should have fire truck pumps certified and tested annually.

This process includes a thorough inspection and operational testing to identify any issues, such as impeller degradation, which can be exacerbated by high elevation. 

These annual tests help departments catch potential problems early, ensuring the pump remains in optimal condition and is always mission-ready.

3. Consistent Maintenance

A fire fighter working on gauges on the side of a red fire truck.Adhering to a strict maintenance schedule allows fire departments to guard against unexpected failures and maintain consistent performance. This approach not only enhances the operational readiness of the fire department but also maximizes the return on investment for firefighting equipment.

Careful planning, annual certification testing and regular maintenance not only ensure the effectiveness of firefighting efforts but also contribute to the overall safety of the community.

What Should Fire Departments at Higher Elevation Ask When They are Deciding Between Different Fire Truck Manufacturers?

Fire truck customers located at higher elevations should consider several specific factors when evaluating fire trucks from different manufacturers. These considerations are crucial to ensure the trucks perform effectively under the unique challenges posed by higher altitudes.  

Here are some key questions to ask fire truck OEMs:

  • Do you take elevation into account in the specification process?
  • How is the fire truck designed to perform at higher elevations?
  • What modifications or technologies do you use to compensate for the thinner air at higher altitudes?
  • Are the pumps designed to handle the lower atmospheric pressures and potential issues like increased cavitation risk at higher elevations?
  • Has the fire truck been tested and certified for use at high altitudes?
  • Can the trucks be customized for high-altitude operation?
  • What kind of support does the manufacturer offer for maintenance and service issues in high-altitude areas?
  • What warranties are offered on the pump, especially considering the extra strain they might be under at higher elevations?
  • Can you provide references or testimonials from other fire departments operating in high-altitude areas? 

Pierce Manufacturing simplifies high-elevation challenges by proactively designing fire trucks equipped to perform in demanding conditions.

For fire departments serving communities in high elevations, Pierce Manufacturing stands out as a leader in providing reliable and efficient fire truck solutions. Each apparatus is not only built to meet the current needs but also to anticipate future challenges and requirements, ensuring longevity and durability in the toughest conditions.

To learn more about how Pierce Manufacturing can enhance your fire department's capabilities in high-altitude areas and to explore customization options for your next fire truck, we encourage you to contact your local Pierce dealer today.

What additional questions do you have about fire truck performance at high elevation? Let us know in the comments.

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About Pierce Manufacturing
Pierce Manufacturing Inc., an Oshkosh Corporation [NYSE: OSK] business, is the leading North American manufacturer of custom fire apparatus. Products include custom and commercial pumpers, aerials, rescue trucks, wildland trucks, mini pumpers, and homeland security apparatus. In addition, Pierce designs its own foam systems and was the first company to introduce frontal airbags and the Side Roll Protection system to fire apparatus. To learn more about Pierce, visit

About Oshkosh Corporation

At Oshkosh (NYSE: OSK), we make innovative, mission-critical equipment to help everyday heroes advance communities around the world. Headquartered in Wisconsin, Oshkosh Corporation employs approximately 17,000 team members worldwide, all united behind a common purpose: to make a difference in people’s lives. Oshkosh products can be found in more than 150 countries under the brands of JLG®, Hinowa, Power Towers, Pierce®, MAXIMETAL, Oshkosh® Defense, McNeilus®, IMT®, Jerr-Dan®, Frontline™ Communications, Oshkosh® Airport Products, Oshkosh AeroTech™ and Pratt Miller. For more information, visit

®, ™ All brand names referred to in this news release are trademarks of Oshkosh Corporation or its subsidiary companies.

Forward Looking Statements

This news release contains statements that the Company believes to be “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact, including, without limitation, statements regarding the Company’s future financial position, business strategy, targets, projected sales, costs, earnings, capital expenditures, debt levels and cash flows, and plans and objectives of management for future operations, are forward-looking statements. When used in this news release, words such as “may,” “will,” “expect,” “intend,” “estimate,” “anticipate,” “believe,” “should,” “project” or “plan” or the negative thereof or variations thereon or similar terminology are generally intended to identify forward-looking statements. These forward-looking statements are not guarantees of future performance and are subject to risks, uncertainties, assumptions and other factors, some of which are beyond the Company’s control, which could cause actual results to differ materially from those expressed or implied by such forward-looking statements. These factors include the Company's ability to successfully integrate the AeroTech acquisition and to realize the anticipated benefits associated with the same; the risks associated with international operations and sales, including compliance with the Foreign Corrupt Practices Act;  the Company’s ability to comply with complex laws and regulations applicable to U.S. government contractors; cybersecurity risks and costs of defending against, mitigating and responding to data security threats and breaches impacting the Company; the Company’s ability to successfully identify, complete and integrate other acquisitions and to realize the anticipated benefits associated with the same; and risks related to the Company’s ability to successfully execute on its strategic road map and meet its long-term financial goals. Additional information concerning these and other factors is contained in the Company’s filings with the Securities and Exchange Commission. All forward-looking statements speak only as of the date of this news release. The Company assumes no obligation, and disclaims any obligation, to update information contained in this news release. Investors should be aware that the Company may not update such information until the Company’s next quarterly earnings conference call, if at all.

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