Smoke Extraction AHU System Design: Statutory Standards 2026
In the 2026 Malaysian engineering landscape, Smoke Extraction AHU System Design (commonly referred to as Smoke Spill Systems) is governed by the Uniform Building By-Laws (UBBL) 2026 and MS 1780:2017/2026. These systems are specialized life-safety assets designed to remove smoke from fire zones—such as large open-plan offices, malls, or basements—to maintain tenable conditions for evacuation.
At EKG (Malaysia) SDN BHD, we design these systems to be Sterile, Silent, and Statutory-Compliant, ensuring they function as high-performance extraction units during an emergency.
1. The Design Mandate: Extraction vs. Purging
As of February 3, 2026, JBPM (BOMBA) requires a clear distinction in the design phase between systems intended for active fire fighting and those for post-fire cleanup.
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Extraction Rate: Under MS 1780, a smoke extraction system must provide a minimum of 10 Air Changes Per Hour (ACH) for the largest fire compartment it serves.
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Temperature Rating: The entire air path—including the fan, motor, and casing—must be certified to operate at 250°C for a minimum of 120 minutes (FRP 120).
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Pressure Management: The design must ensure that the extraction does not create a pressure differential so high that occupants cannot open exit doors (typically limited to 110N of force).
2. Core Engineering Components
A Smoke Extraction AHU differs significantly from a standard cooling unit in its materiality and fail-safe logic.
| Component | 2026 Engineering Standard | Purpose |
| High-Temp Motor | Class H Insulation / IP55 | Ensures the fan continues to run even as the ambient air reaches 250°C. |
| Fire-Rated Ducting | MS 2586:2026 (1.2mm min) | Prevents duct collapse and ensures smoke is vented safely out of the building. |
| VFD "Fire Mode" | Hard-wired Override | Bypasses all internal thermal protection to keep the fan running until structural failure. |
| Fire Dampers | MS 558:2024 Certified | Note: Traditional fire dampers are typically omitted in smoke spill paths to prevent accidental closure during extraction. |
3. Functional Design Sequence (The "Kill-Signal" Protocol)
The integration with the Fire Alarm Monitoring System (FAMS) is the most critical aspect of the design:
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Detection: A signal is received from the building's fire panel or localized Duct Smoke Detectors.
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Comfort AC Shutdown: All standard AHUs receive an Automatic Fire Signal AHU Shut-off to stop the spread of smoke.
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Extraction Initiation: The Smoke Extraction fan ramps up to 100% capacity within 60 seconds.
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Make-Up Air Interlock: Motorized fresh air louvers or dedicated make-up air fans must activate to replace the extracted air, preventing a vacuum effect.
4. Statutory Commissioning & AHU Safety Permit
To finalize the design, EKG engineers coordinate the official witness test with BOMBA:
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Smoke visualization Test: Using non-toxic smoke bombs to verify the effective extraction path and ensure no "dead zones" where smoke could accumulate.
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Static Pressure Audit: Verification that the fan can overcome the resistance of fire-rated ducting and high-temperature louvers.
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Digital Twin Handover (LOD 500): Design parameters and commissioning logs are uploaded to the building’s Digital Birth Certificate for the 5-year periodic statutory audit.
5. Why Partner with EKG (Malaysia) SDN BHD?
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Technical Integrity: Our designs are led by mechanical specialists who understand the complex relationship between thermodynamics, fluid dynamics, and active fire protection.
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EECA 2024 Alignment: We utilize high-efficiency axial or centrifugal fans that meet energy benchmarks during non-emergency "Air Purge" cycles.
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GITA Support: Documented compliance with 2026 BOMBA standards is essential for claiming the 100% Green Investment Tax Allowance.
Is your smoke extraction system a life-safety asset or a statutory liability? Contact EKG (Malaysia) SDN BHD today for a specialized Statutory Smoke Extraction System Design Review.
