The Case for F400: Why Fire Engineers Must Move Beyond F300 in Smoke Control Systems

Introduction

Smoke control systems are essential life safety measures within fire engineering design. One of the critical components in these systems is the smoke-extract fan—responsible for removing hot smoke from escape routes and enabling firefighting access. For years, F300-certified fans (rated to withstand 300°C for 2 hours) have served as a widely accepted standard. However, with advancements in fire safety strategy, EN 12101-3 compliance, and a greater understanding of real-world fire dynamics, a new standard has emerged: F400 smoke-extract fans, rated for 400°C for 2 hours.

This article sets out a clear, technical case for transitioning fully to F400-rated fans in fire safety design, especially in regions where existing specifications continue to reflect earlier standards and fire design approaches.

The Evolution from F300 to F400 in EN 12101-3

The European Standard EN 12101-3:2015 defines the essential performance criteria for powered smoke and heat exhaust ventilators (SHEVs) used in smoke control systems. It mandates type testing of complete fan assemblies under simulated fire conditions, ensuring performance not just in theoretical models, but in real-life, heat-intensive environments.

Classification Overview:

These classifications apply only after the fan assembly (motor, impeller, housing, etc.) has successfully passed full-scale thermal endurance testing. The F400 rating, in particular, is a significant leap in safety—demonstrating a unit’s ability to sustain operation under 400°C heat for a full 2 hours.

Why F400 Is Becoming the Preferred Standard

1. Fire Loads and Car Park Risks Are Increasing

Modern buildings are more densely populated and packed with synthetic materials, which burn hotter and release more smoke than traditional materials. This is especially evident in underground car parks, where vehicles contain large volumes of flammable material and fires can escalate quickly due to limited ventilation and heat entrapment. The thermal environment during a fire has become more extreme, meaning older F300-rated fans may not perform reliably in real-world fire scenarios.

2. Regulatory Direction and Public Infrastructure Considerations

The 2015 revision of EN 12101-3 elevated performance testing and verification standards, placing more emphasis on system integrity and duration of operation. Across Europe, many jurisdictions now favour F400 fans as the default specification for new developments, especially in critical public infrastructure. This includes underground car parks where regulation increasingly reflects the need for sustained high-temperature extraction performance. The widespread use of F400 fans in projects like tunnels, transit stations, and basements illustrates the move toward more robust, standardised protection frameworks.—particularly in:

• Basements exceeding 10,000 m²
• Atriums and shopping centres
• High-rise buildings
• Transport tunnels

This international shift suggests a growing preference for F400-rated systems as the foundation of robust, future-ready smoke control designs.

3. Holistic Fire Safety Design

F400 fans are not standalone upgrades—they enable system-wide resilience. When specifying F400-rated fans, the following benefits are enabled:

• Ducting and cabling can be designed for longer thermal exposure.
• Evacuation models can assume greater tenability periods.
• Fire-fighting access strategies can depend on reliable air movement and smoke clearance.

Moreover, system-wide certification is easier to achieve when the components are aligned at the highest level of performance.

4. Risk Mitigation and Liability

In post-incident analysis, the question is always asked: “Was the equipment specified fit for purpose?” In high-risk environments, specifying F400-rated fans offers additional reassurance and aligns more closely with emerging expectations in performance-based design.

Technical Comparison: F300 vs F400

Smoke Evacuation Report Samples

Warehouse 5000m2

Warehouse 7500m2

Warehouse 10000m2

Where F400 Fans Should Be Standard

Underground Car Parks – Critical Applications for Smoke Extraction

Underground car parks present one of the most challenging environments for smoke control. Fires in these areas often involve vehicle fuel loads, synthetic materials, and enclosed geometries with limited ventilation options. Once ignited, smoke can accumulate rapidly and compromise visibility and breathable air, hindering evacuation and firefighter operations.

F400-certified fans offer the resilience required for these scenarios. Whether in the form of axial extraction systems or jet fans for impulse ventilation, these fans maintain operation at 400°C for 2 hours—ensuring prolonged smoke clearance. Their use has become common practice in international car park designs where compliance with EN 12101-3 and tenability modelling underpins system acceptance.

The reliability of F400-rated fans in sustaining extraction under high thermal stress also supports integration into CO detection and fire alarm-based activation logic, improving overall system responsiveness and safety outcomes.

A Closer Look at Sodeca’s F400 Smoke Extraction Fan Range

As the shift toward F400 certification accelerates, it’s essential for fire engineers to work with manufacturers who not only meet EN 12101-3 standards but also deliver proven performance across various building typologies. Sodeca has established itself internationally as a leader in fire safety ventilation, offering a broad and fully certified range of F400 smoke-extract fans and heat extraction fans.

Axial Smoke Extraction Fans

Sodeca’s axial fan solutions are engineered specifically for high-temperature, emergency scenarios and are tested for 400°C/2h endurance:

• THT Series: Tubular axial fans with short casings, suitable for immersed operation in fire zones. Certified under EN 12101-3 (CPR 0370-CPR-0305).
• THT/CL Series: Long casing variants of the THT series, certified under EN 12101-3 (CPR 0370-CPR-2824).
• THT/ROOF & THT/WALL: Roof- and wall-mounted axial fans with vertical or horizontal discharge. Certified under EN 12101-3 (CPR 0370-CPR-2826).
• CJTHT/PLUS: Acoustically insulated axial fans with built-in attenuators. Certified under EN 12101-3 (CPR 0370-CPR-2827).
• Jet Fans (THT/IMP, CI Series): Impulse and induction fans for car park ventilation and tunnel systems. Certified under EN 12101-3 (CPR 0370-CPR-2829).

Each axial unit is built using corrosion-resistant steel casings, Class H motors (S1/S2 rated), and high-efficiency impellers. These fans are available in single- or two-speed models, with optional reversible airflow and acoustic linings.

Other F400 Fan Solutions

Sodeca also provides a wide variety of centrifugal, roof-mounted, and cabinet-type fans, ensuring versatility across smoke control designs:

• Centrifugal Fans (TCR, CJMP, CJTX-C): Certified under EN 12101-3 (CPR 0370-CPR-2832).
• Cabinet Fans (CJS, CJLINE, CKD, CKDR): Certified under EN 12101-3 (CPR 0370-CPR-2834).
• Roof Fans (CHT, CVT Series): Certified under EN 12101-3 (CPR 0370-CPR-2830).
• Fridge Flap & Cold Room Units: Certified for 400°C/2h operation under EN 12101-3 (CPR 0370-CPR-2831).
• Pressurisation Kits (KIT BOXPDS, KIT BOXSMART): Certified for use in pressurisation systems per EN 12101-6 and EN 12101-3 (CPR 0370-CPR-2833).

Sodeca’s commitment to quality is reflected not only in their EN 12101-3 and ISO 9001:2015 certifications but also in their rigorous in-house testing, including fan balancing, acoustic profiling, and airflow performance validation per ISO 5801.

Conclusion: Aligning with Evolving International Best Practice

Over the years, the specification of F300-rated fans has been common practice, particularly in line with past interpretations of code requirements and historical fire risk assessments. However, the nature of modern fires and the complexity of new buildings have introduced greater challenges and elevated expectations.

As design standards across Europe and the UK increasingly lean toward F400-certified solutions, the opportunity now exists for engineers to align with this evolving best practice. Embracing F400-rated systems ensures greater resilience, more predictable performance during critical fire events, and a future-ready approach to smoke control system design.

Frequently Asked Questions

For more information on smoke control systems, contact Apex Engineering.