Inspection & Testing · Installation · Maintenance
Five-Year Internal & Obstruction Investigation
Every five years NFPA 25 requires someone to open your sprinkler system and look inside it. It is the interval that often goes overdue, and can lead to a pipe replacement if not handled in a timely manner.
Internal obstruction and corrosion assessment on wet, dry, preaction and standpipe systems — the five-year inspection that checks for scale, sediment, microbiologically influenced corrosion and anything else restricting the pipe your sprinklers depend on.
- Standard
- NFPA 25 §14.2 — Internal pipe assessment
- Frequency
- Every 5 years, per system
- Systems
- Wet, dry, preaction, deluge and standpipe
- Also due at 5 years
- Gauges replaced or recalibrated
- Reporting
- Findings per system, with photos
- Coverage
- NJ · PA · DE — statewide
Core services
Inspection and testing, installation, maintenance.
Whether it is one hood or four hundred devices, our inspection, installation and repair services cover it.
The assessment
Opening the system at the required points and reporting on what is inside the pipe.
- Internal inspection at the points NFPA 25 specifies, per system
- Assessment for scale, sediment, corrosion products and biological growth
- Separate assessment per system — a building with multiple risers has multiple due dates
- Photographic record of what was found inside the pipe
- Recommendation on whether a full obstruction investigation is warranted
- Gauges checked at the same visit — they share the five-year interval
When something is found
A finding is the start of a decision, not an automatic repipe. We price the options before anything happens.
- Full obstruction investigation where the assessment warrants it
- Flushing and internal cleaning
- Sectional pipe replacement where corrosion has thinned the wall
- Corrosion-cause analysis so it does not simply return
- Everything priced and approved before we start
Getting the calendar straight
Most owners do not know when their five-year assessments are due, because they were never told at the last one.
- Every system inventoried and given its own five-year due date
- Systems already overdue identified and prioritised
- Multi-system properties sequenced so the work is not all in one year
- Due dates added to your inspection calendar alongside every other interval
Common Questions
Obstruction Investigation — questions we get asked.
What is a five-year internal obstruction investigation?
The code requires that every five years someone opens the sprinkler system and inspects inside the pipe for obstruction and corrosion — scale, sediment, corrosion products and biological growth. It is an assessment first; a full obstruction investigation follows only if the assessment warrants it.
How do I know when mine is due?
Most owners do not, which is the problem — four years pass between reminders and the due date was rarely written down at the last one. Each system carries its own date, so a building with multiple risers has one for each. We inventory them and put every date on one calendar.
What happens if it has never been done?
It is more common than you would expect — we regularly find systems where it has not been performed since installation. The assessment tells you where you stand. Finding corrosion early is the difference between flushing a system and replacing sections of pipe.
Does anything else come due at the same time?
Gauges. They share the five-year interval, so when the internal assessment is overdue the gauges almost always are too — it is the most common pairing in our inspection record. Doing both on one visit is cheaper than two.
We work on what's already in your riser room
No rip-and-replace pitch on the first visit. We hold current manuals and parts references for every line above — when a system genuinely can't be maintained any longer, we'll show you why before we quote a replacement.
Five-Year Internal & Obstruction Investigation in trouble right now?
Call 1-888-306-8430 — the line is answered around the clock by a technician who can access your system information and start guidance on the phone.