EN Fire Rated Duct

Understanding the new EN Regulations

EN Fire Rated Ductwork is the result of 10 years of research and development, produced in an ISO9001 quality control management environment, and installed by certified installers. The old standard of BS476 has been superseded as of July 2013 and has been replaced by the new European Standard EN 12101-7 for smoke extract and EN 15871 for fire ductwork, kitchen extract and pressurisation.

Our ducting has been tested to the latest EN standards and as required by law provide CE marking on products where a harmonised standard exists.

SAFE4 EN | Breffni Air Ltd Specialist Ventilation

The tests vary for different types of duct:

EN 1366 Part 1

Fire Duct, Kitchen Extract & Pressurisation

EN 1366 Part 8

Multi-compartment Smoke Extract

EN 1366 Part 9

Single-compartment Smoke Extract

Performance Criteria

The test specifies the required components measured under prescribed conditions or periods of exposure to fire and includes penetration seals, access doors, fixing supports, unique insulation and sealant.

The system is tested as a whole and all components of the system are tested to ensure they all comply with the fire rating achieved and ultimately the classification declared.

The limiting criteria by which the test results are determined are insulation, integrity, smoke leakage and cross-sectional area.

The ASFP states that the inclusion of non-specific products, material and dimensional modifications may result in the invalidity of the final assembly, thus preventing certification of works.

SAFE4 | Breffni Air Ltd Specialist Ventilation

Penetration Seals

Penetration seals are one of the areas of great concern. They prevent fire spreading from one compartment to another. Failure to achieve this results in test termination.

The ASFP confirms that assemblies associated with block work may not be suitable for dry-lining.

Uniquely built penetration seals withstand severe fire conditions and can be easily installed from components locally available.

Our penetration seals are tested in flexible walls, allowing them to be used in stud partitions, block walls and concrete floors.

Access Doors

Access doors tested are not standard access doors, they are fire rated doors which must withstand temperatures of up to 1000°c.

DW172 states that all interior surfaces of the ductwork shall be accessible for cleaning and inspection purposes. It is recommended that access doors are installed every 3 meters.

These access doors must be the access doors tested during Type A, Type B and Type C both horizontally and vertically.

Our fire rated ducting is designed with a specific emphasis on strength with a minimum load bearing rate per square meter because of its uniquely built structure.

Our EN range is unique in having one of the lowest kg weight per square meter.

Insulation

Fire rated insulation ensures that the temperature measured (outside in Type A, and inside in Type B) does not exceed 140°C mean average above ambient during the test and is deemed automatically failed if any thermocouple rises to 180°C.

Our EN fire rated insulation is a compact calcium- magnesium silicate blanket made from low bio-persistence wool with a thickness of 38mm. It is totally inorganic and exonerated from classification under Nota Q of EU Directive 97/69/EC. It is a lightweight easy to install insulation with an attractive finish similar to the finish of standard thermal insulation.

Integrity

The integrity of the entire system is based on the performance of all elements from penetration seals, to smoke leakage to cross-sectional area.

When all of the components perform to the required standard, only then can the integrity be classified.

Our EN fire rated ductwork has achieved exceptional results in all areas and therefore have a level of integrity others can only hope to achieve.

Our EN fire rated ductwork has achieved a benchmark result for the type of steel ductwork tested which was noted in the independent accredited Warrington Exova test laboratory as not having been achieved before.

Leakage

Leakage is set to different parameters for smoke extract and fire rated duct. Smoke extract is tested to a maximum of 10m3/hr/m2 and a low of 5m3/hr/m2. Fire duct is tested at a higher rate to a maximum of 15m3/hr/m2 and a low of less than 10m3/hr/m2.

Our EN fire rated ductwork received a classification of “S” in both tests, “S” being the highest classification in this category.

Cross-sectional Area

Cross-sectional area is the mechanical stability of the duct being tested. Failure occurs when the duct has a deflection and the cross-sectional area is reduced by more than 10%. This is when the duct weakens as a result of full fire conditions and negative pressure causing the duct to convex. The duct becomes redundant when it changes shape sufficiently impairing its functionality and it loses the ability to perform.

Previously under BS the cross-sectional area was far more generous than the new stringent EN standards. This is because the new EN standard has identified this as a critical requirement to maintain 90% of the cross-sectional area throughout the duration of the test.

Our EN fire rated ductwork meets and exceeds this requirement with an exceptional level of integrity.

Test Pressure

Test pressure is typically carried out at a minimum of 300pa for fire duct and 500pa for smoke extract. During testing there is an option to increase the pressure to a maximum of 1500 pascals.

Our EN fire rated ductwork has tested all ducts to the maximum pressure of 1500pa.

Specification

Safe4 EN

All smoke extract ductwork will be to (hEN) standard 12101-7 and tested to EN 1366-8 for multi-compartment or EN 1366-9 for single compartment.

Where multi-compartment ductwork is required it must be insulated to the same period of time as the compartment through which it passes as required in DW172.

All smoke extract will carry CE Marking from July 2013 and is to be installed under a third party certifier such as Firas as identified in DW144. All ductwork must have classification for testing outside (A), inside (B) and smoke extract (C) in both a horizontal and vertical position.

All ductwork rated “S” for smoke leakage and have been tested to high pressure 1500 PA. All smoke extract will be tested in a flexible wall and be suitable for installation in stud partition, block wall and concrete floor.

Safe4 KE

All fire rated and pressurisation ductwork will be to EN standard 15871 and tested to EN 1366-1 vertically and horizontally for Type A (fire outside) and Type B (fire inside).

All ductwork rated “S” for low leakage. All fire rated ductwork will be tested in a flexible wall and be suitable for installation in stud partition, block wall and concrete floor.

All Kitchen Extract will be to the EN standard 15871 and tested to EN 1366-1, and must be insulated to the same period of time as the compartment through which it passes as required in DW172.

All kitchen extract ducting must be accessible for cleaning and inspection purpose and have a cleaning door (to the same fire rating) installed every 3 meters as stated in DW172.

All ductwork must have classification for testing outside (A) and inside (B) in both a horizontal and vertical position. All ductwork rated “S” for low leakage.

All kitchen extract ductwork will be tested in a flexible wall and be suitable for installation in stud partition, block wall and concrete floor.