Living with a system
I have a system. How do I know it is still working?
The most common failure mode for a mitigation system is not breaking. It is running for years while nobody looks at the gauge, because a spinning fan sounds like a working system and no one told the homeowner otherwise.
The routine below takes about ten minutes a year plus a measurement every couple of years. That is the entire maintenance burden, and it is the difference between owning a system and owning a pipe.
Who this is for. Someone who owns a house with a mitigation system, whether they installed it or inherited it.
The reading order
5 steps, 12 resources. Nothing below is written here — every link goes to the page that holds the substance, and the note under each one says what it adds at that point in the sequence. A hub that restated its own links would just be competing with them.
Learn what normal looks like
You cannot notice a change without a baseline, so this comes first — ideally on the day the system is commissioned.
- What to expect after installation Guide
The sounds, the gauge reading, and the airflow you should record while everything is known to be working.
- Is my system working? Tool
Walks the observable indicators and tells you which combination means act now rather than watch.
- What to expect after installation Guide
The annual routine
Short enough to actually happen. Skipping it is how a failed fan goes unnoticed for a year.
- Annual inspection Checklist
Printable, ten minutes, designed to be done standing next to the system rather than read at a desk.
- How long systems last Guide
What the service life of the whole assembly looks like, so the routine has a horizon.
- Annual inspection Checklist
When something changes
New noise, a gauge that has levelled out, or a fan that has gone quiet each point at a different problem.
- Fan noise and vibration Guide
What each kind of noise usually indicates, and which ones are cosmetic.
- System not working Guide
Symptoms to causes in order of likelihood, so you check the free things first.
- Repair or replace the fan? Tool
For the specific case of a failing fan, weighing age and warranty against the cost of doing it twice.
- Fan noise and vibration Guide
Retesting cadence
A system that has never been retested is an assumption. Measurement is the only thing that converts it into knowledge.
- When to retest Guide
The standing schedule and the events that should trigger a measurement outside it.
- Should I retest? Tool
Whether your situation warrants a measurement now, given what has changed since the last one.
- Post-mitigation testing Guide
How a confirmation measurement should be run, which applies to every retest and not only the first one.
- When to retest Guide
Components and replacement
One part of this assembly has a predictable end of life, and planning for it is cheaper than reacting to it.
- Mitigation System Component and Service-Life Dataset Dataset
Service life by component with provenance stated, useful for deciding what to budget and when.
- Fan technology Newsroom
What is genuinely different about current fans, which matters when a replacement decision comes up.
- Mitigation System Component and Service-Life Dataset Dataset
What you should be able to do afterwards
- Record a baseline you can compare against next year.
- Complete the annual check without needing a contractor.
- Interpret a change in noise or gauge reading correctly.
- Know when the next measurement is due, and why.
Related hubs
- Mitigation systems — A pipe and a fan is not a design. This is the difference.
- Costs and value — We explain what moves a price. We do not publish one we have not measured.
- Testing your home — A number is only as good as the conditions it was collected under.
- All nine hubs — the full learning centre.
Confidence and limits of this page
Every decision resource on this platform states its own boundaries. This is not a disclaimer — it is the part of this hub you should read before relying on it.
- What we knowClaims on this page we stand behind, each traceable to an approved source or to observable structure.
- A running fan does not establish that a system is reducing levels; the pressure gauge and a measurement are what indicate performance.
- Mitigation fans are continuously operating mechanical components with a finite service life, so replacement is a scheduled event rather than a surprise.
- Published guidance recommends retesting after mitigation and periodically thereafter, and after significant changes to the building.
- What we do not knowQuestions you may reasonably have that this page does not answer.
- How long your specific fan will last, which depends on the model, the installation, and the conditions it runs in.
- Whether a change in your gauge reading reflects a system fault or a change in the building, without a measurement to accompany it.
- What research would settle itWhat it would actually take to answer the above — naming it is the difference between honesty and hedging.
- Field failure data across fan models and installation ages, which would replace a general service life with a distribution.
- Paired gauge readings and measurements over time in the same houses, which is what would let anyone interpret a gauge change quantitatively.
- What we do not claimClaims you might expect to find here and will not, with the reason.
- We do not claim a service life figure for any named fan model, because we hold no field failure observations.
- We do not claim a maintenance schedule is required by any authority unless we cite the authority that requires it.
- We do not recommend any maintenance plan, service contract, or product, and we take no position on whether a plan offered to you is priced fairly.
- What we cannot independently verifyFacts this page relies on that we could not confirm ourselves.
- Whether a system in a house you have bought was installed to standard, since the diagnostics that would show it were performed before you owned it.
- Manufacturer service-life claims for specific components, which we have not tested and do not restate as facts.
Sources
- U.S. EPA — Consumer’s Guide to Radon Reduction
- U.S. EPA — A Citizen’s Guide to Radon
- U.S. EPA — Radon
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