Commercial Kitchen & Building Exhaust Systems: SCDF Fire Safety Requirements, Duct Degreasing Frequencies, and Fan Breakdown Prevention

Commercial Kitchen & Building Exhaust Systems: SCDF Fire Safety Requirements, Duct Degreasing Frequencies, and Fan Breakdown Prevention It is 11 AM, forty minutes before lunch service, when the exhaust fan motor seizes. Within minutes, smoke and heat pool in the kitchen, the fire alarm triggers, and staff are evacuating instead of cooking. For F&B operators and facility managers, the mechanical ventilation system is invisible right up until the moment it becomes the only thing that matters. Why the exhaust system is a fire safety system first A commercial kitchen exhaust does not merely remove heat and odour — it carries grease-laden vapour. That grease condenses and accumulates inside the hood, the duct run and the fan itself. Accumulated grease is fuel, and a duct coated in it can propagate a flash fire from a wok flare-up through the entire vertical riser of a building. This is why Singapore's fire safety regime treats kitchen exhaust maintenance as a fire safety obligation, and why SCDF inspections look at duct condition. Facility managers report failing annual inspections over grease leaking through duct seams above ceiling panels — a hazard that had been dripping, unnoticed, for months. How often should ducts be degreased? Frequency follows cooking intensity, the same logic as grease traps: - Heavy-duty operations (wok frying, charbroiling, high-volume frying): typically every 1–3 months. - Moderate operations (general restaurant cooking): every 3–6 months. - Light operations (cafés, low-grease prep): every 6–12 months. The full run matters — hood, filters, duct, and fan. Cleaning only the visible hood while the horizontal duct and rooftop fan cake with grease is the most common false economy in commercial kitchen maintenance. Keep a cleaning record with photos; it is your evidence for SCDF, your insurer, and your mall management. Preventing the breakdown that stops service Exhaust fan failures rarely happen without warning — the warnings are just easy to miss. A preventive programme watches for them: - Belt condition and pulley alignment. V-belts snapping every couple of months is not bad luck; it is misalignment. Proper laser-aligned pulleys and correct tension turn a recurring failure into a non-event. - Motor bearings and current draw. A motor pulling rising current is a motor approaching seizure. Measuring it during scheduled maintenance lets you replace a bearing on your schedule, not at 11 AM on a Friday. - Airflow performance. If smoke lingers in the kitchen, the system may be undersized or the duct static pressure miscalculated — a design fault that no amount of cleaning fixes. New installations that fail to draw smoke usually trace to wrong fan selection for the duct run. - Noise and vibration. Low-frequency rooftop unit noise that draws neighbour complaints — and can breach NEA boundary noise limits — is usually solved with proper isolation mounts and balancing, not replacement. The credential problem that locks contractors out Here is a scenario that surprises many tenants: the contractor arrives for an urgent repair, and mall management turns them away at the loading bay. Commercial buildings and malls routinely require contractors to hold BCA registration in the relevant mechanical workheads (ME01/ME06), bizSAFE certification, and valid insurance before granting access. An uncertified contractor is not just a compliance risk — they may be physically unable to start work when you need them most. The same applies to chilled-water FCU and AHU work in offices, where a condensate overflow can collapse ceiling panels onto workstations. What a maintenance contract should include If you are signing a ventilation maintenance agreement, look for: scheduled degreasing with photo documentation, belt and bearing inspection with replacement thresholds, motor current-draw logging, airflow verification, an emergency response commitment with a stated timeframe, and reports you can hand to SCDF, insurers and mall management. A contract that is just "quarterly servicing" with a one-line invoice protects no one — and leaves you unable to justify the expenditure when management or auditors ask what they are paying for. The difference in cost between a real programme and a paper one is small; the difference in outcomes is the gap between a quiet kitchen and an 11 AM evacuation. Why a regular aircon contractor is not enough Comfort air conditioning and kitchen exhaust are different engineering disciplines. Kitchen systems handle high-temperature, combustible grease vapour; they fall under mechanical ventilation workheads and fire safety considerations that general aircon servicing does not cover. The right question to ask any contractor: What is your BCA registration, and can you show your bizSAFE level and insurance? How AOT handles this Alpha & Omega Trinity is one of Singapore's few contractors holding PUB plumber licence WS16882018, EMA electrical licensing, BCA L1 registration (ME01/ME06/ME12), and bizSAFE Level 3 — so one accountable, fully licensed team handles the job end to end. Alpha & Omega Trinity is a BCA-registered contractor (ME01/ME06/ME12, Grade L1) with bizSAFE Level 3 certification and WICA insurance — the credentials that get us through mall and building security without delay. We provide scheduled exhaust degreasing with photo documentation, fan preventive maintenance with alignment and current-draw checks, and emergency breakdown response for commercial kitchens and building ventilation. For an exhaust system assessment or a preventive maintenance programme, WhatsApp or call +65 8151 8857. We operate Monday to Saturday, 8:00 AM to 5:00 PM (closed Sundays). Frequently Asked Questions How often must F&B grease traps be cleaned in Singapore? PUB requires grease traps at food establishments to be maintained so that discharge meets trade-effluent limits — in practice, most F&B premises need cleaning every 1–4 weeks depending on volume. Neglect causes chokes, odours, and non-compliance. AOT provides scheduled grease trap servicing with disposal documentation for your NEA/PUB records. What happens during a PUB or NEA inspection of my kitchen's grease trap? Inspectors check that the trap is correctly sized, regularly maintained, and that discharge meets limits. Keeping service records is essential. AOT's scheduled maintenance includes service logs you can present on inspection, and our team advises on trap sizing if your kitchen volume has grown.