Gas suppression only works if the gas stays put. A door-fan integrity test proves — without discharging a single cylinder — that your enclosure will hold its agent concentration for the required time. Gemini AMPM tests to ISO 14520 and BS EN 15004 Annex E, finds the leaks, and gives you the pass certificate your insurer wants to see.
A calibrated fan is mounted in the doorway of the protected room, and the space is pressurised and depressurised in turn. From the airflow needed to hold each pressure, we measure the enclosure’s total leakage area — every unsealed cable penetration, gappy door and forgotten void, expressed as one number. Software then converts that leakage into a predicted hold time: how long the room will keep its agent concentration above the minimum at the protected height.
The method comes straight from Annex E of BS EN 15004-1 and ISO 14520-1, and it is the accepted alternative to discharging agent to prove retention — typically ten minutes of hold time is required. No gas is released, nothing shuts down, and the test is normally complete within a couple of hours. It is the cheapest question you will ever ask of a suppression system: would it actually have worked?
Test at commissioning, then at least annually — and again after any change to the enclosure. New cabling punched through a wall, replaced doors, altered partitions, revised ceiling voids: each one changes the leakage picture, and none of them announces itself to your suppression system. Most insurers expect current integrity test records as a condition of cover, and an out-of-date pass is little better than none.
A failed test is not a crisis — it is a to-do list. Our report identifies the leakage paths and the shortfall, and because Gemini runs a FIRAS-certificated passive fire protection team, the remediation — sealing penetrations, dropping in door seals, closing dampers and voids — can be done by us and retested, often in the same visit. You end with a pass certificate and records your insurer can file.
At commissioning, then at least annually — that is the expectation set by ISO 14520 and BS EN 15004, and most insurers treat current test records as a condition of cover. On top of the annual cycle, retest after any work that touches the enclosure: new penetrations, replaced doors, moved partitions, changes above the ceiling or below the floor. If the fabric changed, last year’s pass proves nothing.
You get specifics, not just a fail. The report quantifies the leakage, identifies the likely paths and states the predicted hold time against the required minimum. Remediation is usually unglamorous — sealing cable penetrations, fitting door drop-seals, closing off voids and dampers — and our FIRAS-certificated passive fire team can carry it out and retest, often within the same visit. Most failed rooms can be brought to a pass quickly.
Barely. The door fan needs the doorway and a stable enclosure for the duration — typically a couple of hours — but no agent is discharged, no equipment is powered down and the room’s services keep running throughout. It is dramatically less disruptive than the alternative it replaced, a full discharge test, and vastly less expensive. Most clients schedule it alongside a routine suppression service visit to save a mobilisation.
A named engineer, not a call centre, comes back within 24 hours. Tell us the building and what you’re dealing with, and we’ll scope it properly.