The biggest technical difficulty in a shopping centre is volume. An atrium links floors together and breaks the logic of compartmentation; in exchange, the design rests on keeping smoke above occupant level.
The atrium: smoke control is the centre of the design
In an atrium building the strategy is to hold the smoke layer above the escape routes at a defined height and buy the time needed for evacuation. Three things work together to do that:
- A smoke reservoir. The volume beneath the ceiling where smoke collects, bounded by smoke curtains.
- Mechanical extraction or natural ventilation. The capacity is calculated from the design fire size and the layer height.
- Replacement air. Without controlled inlet at low level to replace the extracted air the system does not work — and it is the most frequently omitted component.
The system is integrated scenario by scenario with fire detection and verified at commissioning against real fan performance.
Sprinklers and smoke control affect each other. Sprinkler water cools the smoke layer and can bring it down. That interaction is taken into account when the design fire size is chosen; the two systems must be designed together, not separately.
Hazard classification inside the units
There is no single class in a shopping centre. Clothing shops, electronics shops, furniture showrooms, restaurants and stores sit on the same floor. The critical point is the back-of-house storage: while the sales floor is ordinary hazard, cartons and plastic packaging stacked to the ceiling in the back store create a high hazard storage condition.
The practical approach is to calculate back-of-house stores with their own hazard class and to limit the storage height in the lease.
Tenant fit-outs: the weakest link
System degradation in shopping centres usually comes not from the design but from tenant fit-outs:
- The ceiling is lowered and the sprinklers stay at the old level.
- A decorative ceiling element shields a sprinkler.
- A partition is added, disturbing the sprinkler distribution and breaching the spacing rules.
- A lighting track or sign passes below the sprinklers.
- A smoke curtain or detector is covered over.
That is why centre management must run a tenant fit-out approval process: every fit-out design is reviewed for fire, the installation is inspected afterwards and the as-built is recorded.
Special areas
| Area | Leading issue |
|---|---|
| Food court | Kitchen hood suppression, grease duct cleaning, high occupant density |
| Cinema | Darkened volume, wayfinding lighting, row-by-row evacuation |
| Children's play area | Occupants needing assistance, fire load of soft-filled materials |
| Plant rooms | Generator, transformer, waste room — separate compartments and suitable suppression |
| Loading dock | Where cartons accumulate; a no-storage rule and regular clearance |
Operational checklist
- Is fit-out approval and post-installation inspection actually running?
- Are storage height limits enforced in back-of-house stores?
- Are smoke curtains and extract fans tested periodically?
- Are food court hood systems and duct cleaning recorded?
- Do fire compartment doors close freely?
- Are loading docks and corridors clear of storage?
Frequently Asked Questions
How does atrium smoke control work?
A smoke reservoir, mechanical extraction or natural ventilation, and controlled replacement air work together to hold the smoke layer above the escape routes. Replacement air is the most frequently omitted component.
Do sprinklers affect smoke control?
Yes. Sprinkler water cools the smoke layer and can bring it down. The two systems must be designed together, not separately.
What is the biggest hazard classification problem in a shopping centre?
Back-of-house storage. While the sales floor is ordinary hazard, packaging stacked to the ceiling in the back store creates a high hazard storage condition.
Why are tenant fit-outs a risk?
Lowered ceilings, shielding decorative elements, added partitions and signage all disturb the sprinkler distribution. A fit-out approval process and site inspection are essential.
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Download MEP Calc on the App StoreThe Turkish Regulation on Fire Protection of Buildings (BYKHY) · NFPA 13 (2025) · NFPA 101 · BS EN 12845:2015+A1:2019 · FM Global Data Sheets. For article numbers, thresholds and exemptions, the current regulation text published in the Official Gazette governs.