Frequently Asked Questions

BS EN 1366 is a family of fire-resistance test standards for service installations. It is not a product approval, and the words “to EN 1366” do not fully specify a ductwork system.

The answer depends on the system function and route. Part 1 covers fire-resisting ventilation ducts, Part 2 fire dampers, Part 8 multi-compartment smoke extraction ducts and Part 9 single-compartment smoke extraction ducts. Other parts cover different service installations.

EN 1366-1 concerns ventilation ducts required to resist fire. EN 1366-8 concerns smoke extraction ducts that pass through another fire compartment and represents a developed fire. EN 1366-9 concerns smoke extraction within a single compartment and represents the developing pre-flashover stage.

They identify different performance criteria: E is integrity, I is insulation and S is smoke leakage. The complete classification must be read, including duration and any orientation, exposure, pressure or application suffixes.

They help describe the application covered by the classification. “ve” and “ho” relate to vertical and horizontal orientation; “multi” and “single” distinguish multi-compartment and single-compartment smoke-control applications.

No. Fire performance normally belongs to a complete tested or assessed system, including duct construction, joints, stiffeners, protection, supports, access panels and penetration details.

Only where the change remains within valid system evidence. Apparently minor substitutions can affect performance, so components and installation details should be checked against the classification, field of application and manufacturer instructions.

Request the applicable test and classification documents, valid direct or extended field-of-application evidence, product information, installation instructions, support and penetration details, and project-specific drawings. Confirm document editions and that the proposed dimensions and arrangement are covered.

Do not simply scale the construction up. Current industry guidance identifies standard direct-application sizes up to 1250 mm × 1000 mm rectangular or 1000 mm diameter circular, although the selected system may be more restrictive. Options may include smaller parallel ducts, a revised route, another evidenced system or a project-specific technical appraisal acceptable to the approving authority.

No. A project-specific engineering judgement may assist an approval discussion, but it does not automatically create an EN classification, extend a product declaration or permit product marking. Its author, technical basis, limitations and acceptance must be clear.

It remains relevant to some existing evidence, specifications and transitional projects, but it is not automatically interchangeable with the EN route. In England, references to BS 476 for fire resistance are scheduled to be removed from Approved Document B on 2 September 2029, subject to transitional provisions. Check the project location, date and regulatory route.

They perform different functions and follow different evidence routes. A fire damper primarily protects a fire-resisting separation; a fire-and-smoke damper also addresses smoke leakage; and a smoke-control damper forms part of a designed smoke-control system. Selection must follow the fire strategy and applicable evidence.

No. The supporting construction, opening, installation method, orientation, fixing and fire-stopping detail must match the applicable evidence and manufacturer instructions.

The inspection regime should follow the current fire strategy, applicable guidance, manufacturer instructions and building risk. Safe access, competent inspection and traceable records are essential; do not adopt an interval without checking the requirements for that building and damper type.

No. The access door is one component of the complete system. Its type, size, position, installation and compatibility must be covered by the evidence for the surrounding ductwork.

BS EN 12101-3 applies to powered smoke and heat control ventilators (smoke extract fans). BS EN 1366-8 and BS EN 1366-9 address the related smoke extract ductwork test routes. The fan and ductwork evidence should be checked separately and then coordinated as one complete smoke-control system.

Yes. DuctFix can discuss Elta smoke fan supply alongside a fire or smoke ductwork enquiry. Provide the required airflow, system pressure, temperature/time classification, fan location, control and power requirements, and the latest drawings through the Project Review. Final selection remains project-specific.

This must not be assumed. Grease-laden kitchen extract presents particular fire, cleaning and maintenance risks, and the design may require continuous fire-resisting ductwork. Follow the fire strategy, kitchen ventilation design and evidence for the proposed system.

There is no responsible one-size-fits-all answer. Inspection and cleaning frequency should reflect cooking type, operating hours, grease accumulation, system condition, fire risk and the applicable TR19 Grease regime. Records should show what was inspected and cleaned.

There must be sufficient safe access to inspect and clean the complete system, including bends, changes in section and obstructed areas. The correct number and positions depend on the route. Openings in fire-resisting ductwork must also remain within the system evidence.

No. Odour control, grease management, cleaning access and fire resistance are related design considerations but perform different functions. Meeting one requirement does not demonstrate the others.

No. This website provides practical guidance and helps identify information that may be missing. It does not replace the standards, tested-system evidence, manufacturer instructions, the project fire strategy or competent professional approval.

Yes. The Project Review questionnaire helps DuctFix understand the proposed system, route, performance, dimensions and available evidence for an initial practical and commercial discussion. It is not a certification or formal design-approval service.