Normative P118-1:2025 and Its Impact on Ventilation and Smoke Extraction Systems: What the Designer Needs to Know

Technical guide for installation engineers, HVAC designers and ISU technical managers regarding the new mechanical smoke extraction requirements

Why P118-1:2025 Matters for Every Ventilation Project in Romania

The P118-1:2025 normative on fire safety in buildings is the most important regulatory document in the field updated in recent years, coming to replace and update P118-99 provisions after two decades. Its entry into force changes the calculations for tens of thousands of installation projects underway or planned — from underground car parks and shopping centres to office buildings, hospitals and collective residential buildings.

For the installation designer, P118-1:2025 is not a document to read once and forget. It is the legal framework that determines which types of fan can be installed, what certifications they must hold, how smoke extraction systems are sized and what documentation is required for the ISU approval.

Basic Principles of Smoke Extraction per P118-1:2025

The normative defines smoke extraction as the extraction of smoke from the upper part of the fire compartment (located at minimum 1.80 m above floor level), in order to ensure conditions for user evacuation.

The smoke and hot gas extraction system can be achieved with:

• Organised natural draught — through smoke vents with automatic opening in roof or exterior walls
• Mechanical draught — through fire-rated fans and certified ductwork
• Mixed systems — combination of both approaches

System design can be done alternatively per the normative and/or per standards SR CEN/TR 12101-5:2007 (CFD calculation guide) and SR EN 12101-6:2005 (smoke control system specifications).

What Changed vs. P118-99: Key Points for Designers

1. Updated fire resistance classes for equipment

P118-1:2025 aligns terminology and requirements with European EN 12101 standards. Smoke extraction fans must be certified per EN 12101-3, with classes:

• F300/120 — operation at 300°C for 120 minutes (fans in the risk zone)
• F400/120 — operation at 400°C for 120 minutes (final extraction fans, car parks)
• F200/120 — operation at 200°C for 120 minutes (specific applications)
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2. Mandatory CFD calculation for certain configurations

For spaces with complex geometry (atriums, multi-level car parks, shopping centres), P118-1:2025 explicitly recommends validation through CFD simulation (SR CEN/TR 12101-5), not just analytical calculation.

3. Mandatory dual command — automatic and manual

The automatic command of smoke extraction systems shall be duplicated by manual centralised command from the UCMS (Manual Centralised Security Command Unit) of the fire control room.

4. Electrical supply requirements

Smoke extraction fans shall be powered from both the primary source and a backup source (generator or UPS with sufficient autonomy).

5. Fire dampers and shutters

Smoke extraction openings must be closed with fire-tight E shutters (on fresh air supply ducts) and EI fire-resistant shutters (on smoke extraction ducts). These shutters are closed in standby position and open on command in case of fire.

Consolidated Table: P118-1:2025 Requirements by Building Type

What Types of Fans Are Compliant with P118-1:2025

P118-1:2025 does not specify brands or models, but performance classes per European standards. Any fan installed in a smoke extraction system must have:

• CE certificate per EN 12101-3
• Declaration of Performance (DoP) with the F300 or F400 class explicitly stated
• Test report from a notified certification body

Smoke extraction fans available on ventilation.ro

ventilation.ro holds over 400 products in the "Smoke extraction in case of fire" category, covering all necessary configurations:

Fans in the risk zone (mounted inside the protected space): Includes axial and centrifugal Jet Fans (F300/120), fire-rated incorporated fans and duct fans with F300 certification.

Final extraction fans (mounted outside the risk zone): Fire-rated rooftop fans (F400/120), fire-rated centrifugal BOX fans and F400 duct axial fans.

Common Design Errors and How to Avoid Them

Error 1: Installing a standard fan instead of a certified F300/F400 one A standard industrial fan, however robust, is not designed to operate at 300–400°C. The smoke extraction system becomes non-functional precisely when it is most needed. Always check the EN 12101-3 certificate before specifying.

Error 2: Sizing without CFD calculation in complex spaces Simple analytical calculation does not account for space geometry, obstacles, structural columns or fire source distribution. For car parks with more than one level or atriums, CFD calculation is practically mandatory to obtain the ISU approval.

Error 3: Uncertified smoke extraction ductwork Ducts through which smoke circulates must be Class A1 or A2-s2,d0 fire-rated materials, fire-tight, with optimally sized cross-sections. Standard flexible ductwork or PVC is not permitted in smoke extraction systems.

Error 4: Absence of backup power supply ISU checks at handover whether smoke extraction fans are connected to the generator or UPS. A smoke extraction system powered exclusively from the normal network is non-compliant.

Documentation Required for ISU Approval

• Smoke extraction system layout with all equipment positions
• Airflow calculation per smoke extraction zone
• Technical datasheets and EN 12101-3 certificates for all fans
• Automatic and manual command (UCMS) schematic
• Electrical supply schematic from primary and backup source
• CFD study (where required)
• Declarations of conformity for smoke extraction ductwork

Conclusion

ventilation.ro provides over 400 products certified for smoke extraction in case of fire, with complete technical documentation (datasheets, declarations of performance, EN 12101-3 certificates) available for download on each product page.

Contact the team of specialists at +40 722 667 239 for technical advice on equipment selection per P118-1:2025.