AGF Manufacturing explores NFPA 25 and the role of dependable system components in fire sprinkler systems
Fire sprinkler systems are often described as “silent guardians.” When designed and installed correctly, they wait, sometimes for decades, without drawing attention to themselves.
But this quiet reliability can be deceptive.
A fire sprinkler system that is not regularly inspected, tested and maintained may look perfectly fine right up until the moment it is needed most.
That is why Inspection, Testing and Maintenance (ITM), as required by NFPA 25, is one of the most critical disciplines in the fire protection industry.
This article takes an industry-focused look at ITM: why it exists, what NFPA 25 requires, common challenges faced by contractors and building owners and how thoughtful component selection can make long-term compliance safer, easier and more reliable.
While products alone never replace proper ITM practices, the right system components can support technicians in performing consistent, code-compliant work year after year.
The purpose of NFPA 25
NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, exists for a simple but essential reason: fire sprinkler systems are mechanical systems, and all mechanical systems degrade over time.
Corrosion, scale, freezing conditions, vibration, accidental damage and unauthorised modifications all pose real threats to sprinkler system performance.
NFPA 25 does not assume that the system will remain functional simply because it passed acceptance testing.
Instead, it recognises that reliability must be verified continuously throughout the life of the system.
The standard establishes minimum requirements for:
- Inspection: Visual examinations to identify obvious deficiencies or changes in condition
- Testing: Operational checks that confirm components function as intended
- Maintenance: Repairs or corrective actions that restore system readiness
Together, these activities form a feedback loop.
Inspections identify potential problems, testing confirms performance and maintenance closes the gap before failures occur.
Why ITM is increasingly critical
Modern buildings place growing demands on fire sprinkler systems.
Mixed-use occupancies, complex hydraulics, energy-efficient construction and tighter building envelopes all influence system behaviour.
At the same time, many facilities are operating with reduced maintenance staff and tighter budgets.
In this environment, ITM is not simply a regulatory obligation, it is a risk management strategy.
Several industry trends are elevating the importance of ITM:
Aging Infrastructure
A significant portion of installed sprinkler systems in North America are well past their original design life.
Older systems may include obsolete components, undocumented modifications, or materials that no longer meet current expectations for durability and serviceability.
Corrosion and water quality issues
Corrosion-related failures continue to be one of the leading causes of sprinkler system impairment.
Poor water quality, trapped air, MIC (microbiologically influenced corrosion) and stagnant branch lines all increase the likelihood of leaks or obstructions.
NFPA 25 places growing emphasis on internal pipe condition assessments and corrective actions.
Increased enforcement and documentation
Authorities Having Jurisdiction (AHJs) are paying closer attention to ITM records.
Deficiencies that were once overlooked are now more likely to result in citations, system impairments, or required corrective work.
Accurate testing and clear documentation matter more than ever.
Key ITM requirements that matter most in the field
While NFPA 25 is comprehensive, several areas consistently demand attention during routine ITM activities.
Valves: Visibility, accessibility and operability
Control valves are among the most critical components in sprinkler systems.
NFPA 25 requires regular inspection to confirm valves are:
- In the normal operating position
- Properly supervised or locked
- Accessible and clearly identified
Testing ensures valves operate smoothly through their full range of motion.
Maintenance addresses leaks, packing issues, or mechanical damage.
Valves that are difficult to operate or poorly labelled increase the risk of accidental shutdowns or delayed response during emergencies.
Drains and low-point management
Auxiliary drains or low-point drains play a key role in removing trapped water or condensation from dry and pre-action systems.
NFPA 25 requires periodic draining.
Inadequate draining can lead to frozen auxiliary drains that break, can cause flooding and false system trips.
From an ITM perspective, drains that are labelled and easy to locate and operate, reduce both labour time and the risk of incomplete maintenance.
Air and pressure management
Trapped air in wet systems contributes to corrosion, water hammer and inconsistent system performance.
NFPA 25 testing activities, such as main drain tests and trip tests, often reveal air-related issues indirectly through slow pressure recovery or abnormal readings.
Components that support effective air management can help stabilise system pressures and improve long-term reliability, even though they are not a substitute for proper system design or testing.
Why component selection matters
NFPA 25 governs what must be done, but it does not dictate how easy or difficult compliance will be.
That is largely determined during system design and installation.
From an ITM standpoint, the best systems share several characteristics:
- Clear identification of components
- Safe, ergonomic access to valves and drains
- Durable materials suited to the system environment
- Consistency across installations
When systems are designed with ITM in mind, inspections are faster, testing is more accurate and maintenance activities are less disruptive to building operations.
The role of purpose-built fire protection components
Within the fire sprinkler industry, certain components are specifically engineered to support inspection, testing and maintenance activities.
These components are not “extras”.
They exist to address real-world challenges encountered in the field.
Integrated test and drain assemblies
Test and drain valves simplify NFPA 25 testing by combining multiple functions into a single, clearly labelled assembly.
By reducing the number of separate connections and valves, they help minimise potential leak points and streamline annual testing procedures.
From an ITM perspective, fewer connections mean fewer opportunities for failure and fewer variables during inspections.
Additionally, these valves can incorporate the required pressure relief valves.
Newer pressure relief valves have features to isolate them from the system for the required hydrostatic test.
Auxiliary and drum drains
Purpose-built auxiliary drains help technicians remove trapped water from low points efficiently and safely.
Designs that allow automated draining and heated cabinets reduce the likelihood of incomplete draining or potential freezing.
Automatic air vents
Automatic air vents, when properly applied, assist with ongoing air management by releasing trapped air in wet system during system filling and operation.
While not a replacement for proper testing, they can support system stability and reduce long-term corrosion risks.
Inspector’s Test Assemblies
Clearly identifiable and properly sized inspector’s test connections are essential for verifying system performance.
Assemblies designed with accessibility and visibility in mind support consistent, repeatable testing in accordance with NFPA 25.
Manufacturers such as AGF have focused on developing components specifically for these applications, informed by decades of field experience.
When selected appropriately, these products can support, not replace, the disciplined ITM practices required by the standard.
Common ITM challenges and how the industry can address them
Despite clear standards, ITM challenges persist across the industry.
1. Incomplete or inconsistent inspections
Rushed inspections or unfamiliarity with system layouts can result in missed deficiencies.
Clear labelling, standardised assemblies and consistent component placement help reduce reliance on institutional knowledge.
2. Testing that becomes “check-the-box”
Testing performed without understanding system intent can miss underlying problems.
Components that provide clear flow paths, accurate discharge points and repeatable operation support meaningful testing rather than superficial compliance.
3. Deferred maintenance
Maintenance is often postponed due to cost or operational concerns.
Systems designed with serviceability in mind, using components that are designed to extend the life of a system, like air vent, reduce the burden of corrective work and encourage timely repairs.
ITM as a shared responsibility
NFPA 25 places responsibilities on multiple stakeholders:
- Building owners must ensure ITM is performed and documented
- Contractors and service providers must execute inspections and tests competently
- Manufacturers must supply components that perform reliably over decades
- AHJs must enforce requirements consistently
When any link in this chain fails, system reliability suffers.
Thoughtful collaboration across these roles strengthens overall fire protection outcomes.
Raising the bar for long-term reliability
The fire sprinkler industry continues to evolve, but the core mission remains unchanged: systems must work when lives and property are at risk.
NFPA 25 provides the framework to verify that readiness, but compliance is only as effective as the systems and components being maintained.
By designing and installing systems with ITM in mind, selecting purpose-built components and treating inspection, testing and maintenance as an ongoing discipline rather than a five-year obligation, the industry can improve system reliability across the entire building lifecycle.
In the end, ITM is not about paperwork or procedures.
It is about confidence, the quiet assurance that when the sprinkler is activated and water is demanded, the system will respond exactly as intended.