Terin Hopkins, NFSA Manager of Public Fire Protection

Standpipe systems are among the most important life safety features in a building. They provide firefighters with an immediately available water supply at strategic locations throughout a structure, eliminating the need to advance long hose lays from the exterior. When operating properly, standpipe systems improve fire department effectiveness, reduce deployment times, and enhance firefighter safety.

Because these systems are expected to perform under the most demanding fire conditions, periodic inspection, testing, and maintenance are essential. The 2026 edition of NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems establishes the minimum requirements for verifying that standpipe systems remain operational throughout their service life.

Unfortunately, many existing standpipe systems, particularly those installed decades ago, present unique challenges. Original hydraulic calculations, acceptance test records, and as-built drawings are often unavailable.

In addition, some jurisdictions conduct only partial-flow testing rather than the full-demand testing required by NFPA 25. These abbreviated tests creates a false sense of confidence while leaving significant deficiencies undiscovered.

This article reviews the 2026 NFPA 25 testing requirements, explains how to evaluate systems when original design documentation is missing, and discusses considerations for aging high-rise buildings.

Understanding the Difference Between Manual and Automatic Standpipe Systems

A common misconception is that all standpipe systems are tested the same way. In reality, NFPA 25 establishes different testing requirements based on whether the system is manual or automatic.

Manual Standpipe Systems

Manual standpipe systems may be either wet or dry, but neither is provided with an automatic water supply capable of meeting the required standpipe demand. A manual wet system contains water under normal conditions, while a manual dry system remains empty until supplied by the fire department. In both cases, responding firefighters connect a fire apparatus to the fire department connection (FDC) and pump water into the system at the pressure and flow needed to support interior firefighting operations.

Because the fire department provides the water supply, NFPA 25 does not require a five-year flow test to verify hydraulic performance. Instead, every five years these systems must undergo a hydrostatic test to verify the structural integrity of the piping, fittings, valves, and related components.

This distinction is important. A hydrostatic test confirms the system can withstand pressure without leakage or failure; it does not evaluate the ability to deliver the required water supply.

Automatic Standpipe Systems

Automatic standpipe systems are connected to an automatic water supply, such as a municipal water system, gravity tank, pressure tank, or fire pump, capable of automatically supplying the required standpipe system demand without fire department intervention.

Because these systems are expected to provide water immediately when a hose valve is opened, NFPA 25 requires a much more comprehensive evaluation. Every five years, automatic standpipe systems must undergo a full-demand flow test that verifies the available pressure and flow at the hydraulically most remote hose connection. This confirms that the entire system, including the water supply, underground piping, fire pump, risers, valves, and standpipe piping, continues to perform as designed.

Unlike a hydrostatic test, a flow test evaluates actual system performance under operating conditions.

Full-Demand Flow Testing Is Essential

A concerning trend in some jurisdictions is the use of partial-flow testing during the required five-year inspection. In many cases, inspectors open a single hose outlet, record residual pressure, and conclude that the system is satisfactory.

While this approach may reduce water discharge and simplify testing, it does not satisfy the intent of NFPA 25 for automatic standpipe systems.

Standpipe systems behave very differently at low flow than they do at full system demand. Friction loss increases significantly as flow rises, pressure-reducing valves operate differently under full demand, and fire pumps that appear acceptable at low flow may fail to maintain adequate pressure when delivering the required full system demand. Municipal water supplies can also experience pressure losses that become apparent only during high-flow conditions.

Simply demonstrating that water flows from a hose valve does not verify that the standpipe system will perform during an actual fire. The purpose of the five-year test is to confirm that the system can deliver its required design demand. For that reason, automatic standpipe systems should always be tested at their full required flow whenever the five-year performance test is conducted.

When Original Design Documentation Is Missing

One of the most common challenges involves older buildings where hydraulic calculations, acceptance test reports, or as-built drawings no longer exist. Although the absence of documentation complicates testing, it does not relieve the building owner of the responsibility to demonstrate that the standpipe system can perform as intended.

The first step is determining the approximate construction date and identifying the edition of NFPA 14 in effect at the time of installation. Historical editions establish the original design criteria and provide the best basis for estimating the required performance.

For automatic standpipe systems, historical design requirements generally fall into one of two acceptable performance categories:

• Pre-1993 NFPA 14: Minimum 65 psi residual pressure at the hydraulically most remote two hose outlets while flowing 750gpm for buildings with two standpipes or 1,000gpm for buildings with three or more standpipes.
• 1993 and later editions of NFPA 14: Minimum 100psi residual pressure at the hydraulically two most remote hose outlets while flowing 750gpm for buildings with two standpipes or 1,000gpm for buildings with three or more standpipes.

Accordingly, when evaluating an automatic standpipe system without original documentation, the expected performance will generally fall into one of these two categories: 65psi at 750–1,000gpm or 100psi at 750–1,000gpm, depending on the applicable edition of NFPA 14.

Whenever possible, additional information should be gathered from building permits, fire department records, archived plans, insurance reports, renovation documents, or previous inspection records. Evaluators should also consider building height, occupancy, the number of standpipes, and whether the system is manual or automatic, since these factors directly influence expected requirements.

If documentation cannot be located, a qualified fire protection engineer should evaluate the system using the installation criteria in effect when the building was constructed and establish a reasonable estimate of the original system demand for comparison during the five-year flow test.

The goal is not simply to record the pressure and flow the system happens to produce. The objective is to verify that the standpipe system still provides the level of performance for which it was designed and can support effective interior firefighting operations.

Evaluating Older Standpipe Systems

This philosophy is particularly important for standpipe systems installed during or before the 1950s. Many were originally designed to deliver only 500gpm at 50psi residual pressure. While these systems may remain legally existing installations and current codes generally do not require replacement solely because of age, their performance often falls well below what is considered adequate for today’s fire service.

The five-year flow test provides an excellent opportunity for owners, insurance companies and Authorities Having Jurisdiction (AHJs) to evaluate not only whether the system complies with its historical design criteria, but also whether that level of performance continues to provide a reasonable minimum margin of safety for modern firefighting operations.

Why neither NFPA 14 nor NFPA 25 establishes automatic retrofit triggers requiring these older systems to be upgraded. However, AHJs should carefully consider requiring improvements when testing demonstrates that a system cannot adequately support current fire department operations.

A standpipe system capable of delivering only 50psi at a total flow of only 500gpm may have met the requirements of a code written more than 70 years ago, but that does not necessarily mean it provides an acceptable level of protection today. Modern fire departments routinely encounter larger buildings, higher fuel loads, and more demanding fire conditions than were envisioned when these systems were installed.

Whenever significant renovations occur, occupancy hazards increase, or major deficiencies are identified during testing, AHJs should strongly consider requiring upgrades that provide performance consistent with modern standpipe design, either 65psi or 100psi residual pressure while flowing 750 to 1,000gpm, as appropriate. Although current standards do not mandate these upgrades, they can substantially improve occupant & firefighter safety, liability and suppression capabilities.

Evaluating Fire Pump Performance in Older High-Rise Buildings

Many older high-rise buildings present another significant challenge. Although the fire pump may have satisfied the original design criteria when installed, changes over time, including renovations, aging equipment, modifications to the water supply, or increased system losses, may prevent it from producing the required pressure and flow today.

During a five-year flow test, inspectors occasionally discover that the fire pump can no longer meet the historical standpipe demand. Simply documenting the measured performance is not sufficient. The deficiency should be evaluated by a qualified fire protection engineer to determine the cause and assess its impact on firefighter operations.

Common causes include:

• Fire pump deterioration or worn impellers.
• Changes in the municipal water supply.
• Closed or partially closed valves.
• Increased friction losses resulting from piping modifications.
• Pressure-reducing valve problems.
• Building renovations that altered hydraulic demand.

Based on this evaluation, corrective actions may include repairing or replacing the fire pump, upgrading pumping equipment, adjusting or replacing pressure-reducing valves, improving the water supply, or modifying the hydraulic system.

Reduced performance should never be accepted simply because a building is old. Standpipe systems exist to protect occupants & firefighters during the most demanding fire conditions, and deficiencies identified during testing deserve careful engineering evaluation.

Documentation Is Critical

Every five-year standpipe test should produce complete documentation, including:

• Test date and location.
• Personnel performing the test.
• Water supply conditions.
• Static and residual pressures.
• Flow rate.
• Fire pump performance, when applicable.
• Hose valve locations tested.
• Test equipment used.
• Deficiencies or impairments identified.
• Recommended or completed corrective actions.

Comprehensive records establish a valuable performance history, support future inspections, and provide engineers with critical information when troubleshooting system deficiencies.

Conclusion

The five-year testing requirements in the 2026 edition of NFPA 25 are intended to do far more than satisfy a regulatory obligation. They verify that standpipe systems will perform when firefighters depend on them most.

Manual standpipe systems require hydrostatic testing to confirm structural integrity. Automatic standpipe systems require full-demand flow testing to verify that the installed water supply continues to deliver the pressure and flow necessary for effective fire suppression.

Partial-flow testing should never replace the full-demand testing required by NFPA 25. Likewise, when original design documentation has been lost, owners, contractors, inspectors, and AHJs should reconstruct the original design basis using historical NFPA 14 requirements, available building records, and qualified engineering analysis.

Finally, deficiencies identified during testing, particularly in older high-rise buildings with aging fire pumps or legacy standpipe systems, should not simply be accepted because of the building’s age.

While NFPA 14 and NFPA 25 do not establish mandatory retrofit triggers, the five-year flow test provides an ideal opportunity for AHJs and building owners to evaluate whether older systems continue to provide an acceptable minimum level of protection.

Where testing demonstrates inadequate performance, upgrades to modern standpipe design criteria should be strongly considered to improve firefighter safety and ensure these systems remain effective for today’s fire service.

A standpipe system is more than a code requirement—it is a critical link between a building’s fire protection infrastructure and the firefighters who rely on it. Comprehensive testing, thorough documentation, and sound engineering evaluation help ensure that this vital system will perform when lives are on the line.

Terin Hopkins has 40 years of experience in public safety, fire protection, and life safety policy. He currently serves as the Manager of Public Fire Protection for the National Fire Sprinkler Association (NFSA), where he leads technical support and advocacy efforts nationwide, working closely with fire departments, code and standard, and policymakers to improve fire protection infrastructure and compliance. He represents NFSA on NFPA and UL technical committees, including NFPA 14 Standard for the Installation of Standpipe and Hose Systems.