What Is a Grease Trap?
A grease trap — also called a grease interceptor or FOG interceptor — is a plumbing device installed between a commercial kitchen’s drainage outlet and the municipal sewer network. Its sole function is to capture fats, oils, and grease (FOG) from kitchen wastewater before they enter and solidify inside the drainage infrastructure.
Without a grease trap, hot FOG from cooking flows into the drain, cools, solidifies, and accumulates on pipe walls. Over time this causes blockages that can affect an entire drainage district, not just one restaurant. Dubai Municipality requires every commercial kitchen on the city’s drainage network to have a DM-approved grease interceptor installed — with no exemptions for small operators or low-volume kitchens.
How Does a Grease Trap Work?
The physics behind a grease trap is straightforward: FOG is less dense than water and floats. A properly designed trap exploits this property in three stages:
- Inlet baffle: Wastewater from the kitchen enters through an inlet pipe positioned below the surface of the water in the trap. The downward direction slows flow velocity and allows solids to sink to the bottom.
- Retention zone: The slow-moving water sits in the trap long enough for grease to rise to the surface, where it accumulates as a floating layer. Solids (food particles, sediment) sink and collect at the bottom.
- Outlet baffle: Relatively clean water exits through an outlet pipe that draws from the middle of the water column — below the grease layer and above the sediment layer — before discharging to the municipal sewer.
Efficiency depends entirely on the trap being emptied regularly. Once the grease layer and sediment layers consume more than 25% of the trap’s working volume, FOG begins to carry over into the outlet and bypass the system. This is why professional cleaning at the correct frequency is both a legal requirement and an operational necessity.
Types of Grease Traps Used in the UAE
| Type | Capacity | Typical Use | Notes |
|---|---|---|---|
| Hydromechanical (under-sink) | 50 – 200 L | Small café, juice bar, food truck | Compact, installed under or near the sink unit |
| Gravity interceptor (in-ground) | 200 – 3,000 L | Mid-size restaurant, food court stall | Buried outside or in kitchen floor; requires vehicle access for pump-out |
| Large in-ground interceptor | 3,000 – 10,000+ L | Hotel main kitchen, hospital, large mall | Engineered installation; sometimes segmented into two chambers |
| Automatic grease removal unit (AGRU) | Varies | High-volume kitchens with tight space | Motorised skimmer removes grease automatically; requires less frequent manual pump-out |
All units supplied and installed by GTC are DM-approved. If your operation does not yet have a grease trap or needs an upgrade to meet capacity requirements, see our grease trap supply and installation service in Dubai.
What Happens Without a Grease Trap?
Operating a commercial kitchen in Dubai without a functioning grease interceptor carries immediate legal and operational consequences:
- DM inspection fines: A minimum AED 5,000 fine for kitchens without an installed unit, rising to AED 50,000 for drainage violations or repeat offences.
- Closure order: Dubai Municipality can issue a closure order that prevents trading until the kitchen is fully compliant.
- Trade licence impact: Persistent non-compliance is flagged to the Food Safety Department and affects trade licence renewal.
- Drain blockages: Solidified grease downstream of the kitchen causes backups that can shut down multiple outlets in the same building.
For the full penalty schedule and compliance checklist, see our Dubai Municipality grease trap requirements guide.
How Often Must a Grease Trap Be Cleaned in the UAE?
Dubai Municipality requires monthly cleaning for high-volume F&B outlets (200+ meals per day) and quarterly cleaning for low-volume operations. The cleaning must be carried out by a licensed contractor who issues a DM-accepted compliance certificate on the day of service — self-cleaning is not accepted as evidence of compliance.
GTC is a DM-licensed contractor operating across all seven UAE emirates. To book a cleaning service or set up a maintenance contract, call +971585707110.