F300 and F400 are temperature classes for smoke extract fans, describing how long a fan keeps running while handling hot smoke in a fire. Rapid Cool supplies smoke extract and car park ventilation fans to MEP contractors and consultants across Dubai, Abu Dhabi and Sharjah, and the class on the schedule decides which fans can be offered at all. An F400 fan is not a standard extract fan with a certificate attached. It is a different build, tested as an assembly, and it cannot be substituted late in a project. Send your fan schedule to Rapid Cool and the offered units can be matched to the stated class.
What the F Class Actually Means
The F class states a temperature and a time for which the fan must continue to move air, tested to EN 12101-3, the European standard for powered smoke and heat exhaust ventilators. The common classes read as a temperature in degrees Celsius followed by the duration in minutes, so F300 120 means 300 degrees for 120 minutes and F400 120 means 400 degrees for 120 minutes.
Two points matter commercially. The class applies to the tested assembly, which means the fan with its specified motor, mounting and wiring arrangement, not to the impeller alone. And the test is about continued operation, not survival, since a fan that seizes after twenty minutes has failed even if it is still physically intact.
Which Class Does a Project Need?
The required class comes from the fire strategy for the building, not from the fan supplier. A consultant or fire engineer sets it from the design fire size, the expected smoke temperature at the extract point and the evacuation time the strategy depends on.
As a general pattern, extract points close to the likely fire, such as a car park or an atrium at low level, attract the higher classes. Extract from a route where smoke has cooled on the way, or where the fan sits well away from the fire source, may be specified lower. Where a schedule is ambiguous, treat it as a question for the fire engineer rather than an engineering judgement to make at the procurement stage, because getting it wrong is a replacement rather than an adjustment.
What Changes Inside an F Rated Fan
A smoke rated fan differs from a standard extract fan in the motor position, the materials and the way it is wired.
| Element | Standard extract fan | F300 or F400 smoke extract fan |
|---|---|---|
| Motor | Standard duty, often in the airstream | Rated for the test temperature, or mounted out of the airstream |
| Bearings and lubrication | Standard grease | High temperature grease specified for the class |
| Cabling and terminations | Standard | Fire rated cable and terminal box suitable for the duty |
| Casing and fixings | Standard steel and coatings | Materials and coatings tested at temperature |
| Certification | Performance data only | Test certificate for the assembly to EN 12101-3 |
The practical consequence is that an F rated fan cannot be created by swapping a motor on site. The certificate covers the assembly as tested, so any change to the motor, the mounting or the terminal arrangement invalidates it.
Dual Duty Fans for Car Parks and Basements
Many car park fans run two duties from one unit: daily ventilation to control carbon monoxide at modest airflow, and smoke extract at full airflow in a fire. Dual speed or variable speed operation delivers both from the same fan, which saves the cost and space of a second system.
Check two things on a dual duty selection. The fan has to meet the smoke extract airflow and pressure at the high duty, since sizing it around the day to day ventilation load leaves it short when it matters. And the control arrangement has to force the fan to full speed on a fire signal, overriding the carbon monoxide control, with that override wired so it cannot be defeated by the normal control system. Our guide to car park jet fans and ducted ventilation covers the system arrangements this applies to.
Commissioning and Documentation
The documentation is part of the deliverable on a smoke extract fan, and missing paperwork delays handover as effectively as a missing fan. Expect to hand over the EN 12101-3 test certificate for the supplied assembly, the fan performance curve showing the operating point at the smoke extract duty, the motor data, and the commissioning record showing measured airflow against design.
Ask for the certificate at the quotation stage rather than at delivery. A supplier who can produce the tested assembly documentation up front is offering a fan that has actually been tested to the class, which is not always the case where a datasheet simply carries the class as a label.
Common Mistakes on Smoke Extract Fan Procurement
- Treating the class as a label rather than a tested assembly, and accepting a substitution without new certification
- Sizing a dual duty fan on the ventilation duty and discovering it is short on the smoke duty
- Omitting the fire rated cable and terminal arrangement that the test certificate depends on
- Leaving the carbon monoxide control able to override the fire signal instead of the reverse
- Selecting on airflow alone without checking the operating point against the fan curve at the real system resistance
Rapid Cool supplies smoke extract and ventilation fans from SODECA, whose range includes units certified for high temperature duty. Full ranges are on the SODECA fan range and the ventilation fan suppliers in UAE pages, and general extract duties are covered on the exhaust fan suppliers in Dubai and the UAE page.
FAQs
Is F400 always better than F300?
No. The class has to match the fire strategy. Specifying F400 where the strategy calls for F300 adds cost without adding compliance, and specifying F300 where F400 is required will fail review.
Can a standard extract fan be upgraded to F300?
Not on site. The class certifies the tested assembly, so a motor or terminal box change on an uncertified fan does not produce a rated unit.
Does a smoke extract fan need a dedicated power supply?
The supply and cabling have to remain functional for the rated duration, which normally means fire rated cable on a protected circuit. The fire strategy and the electrical design set the detail.
Who decides the F class on a UAE project?
The fire engineer or consultant responsible for the fire strategy, with authority approval. Confirm the class in writing before the fans are ordered, since a late change means replacement rather than modification.