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EducationJune 2026 · 7 min read

Grease Trap vs Hood Cleaning: What Is the Difference and Do You Need Both?

Restaurant owners often confuse grease traps and hood cleaning — or assume they are related. They are not. They address entirely different grease streams, answer to different agencies, and have separate compliance requirements. Here is the clear breakdown.

In This Guide

  1. What Each System Does
  2. Two Different Types of Grease
  3. Separate Compliance Requirements
  4. Grease Trap Basics for San Diego Operators
  5. Hood Cleaning Basics
  6. Do You Need Both?
  7. FAQ

What Each System Does

Grease Trap
A plumbing interceptor installed in the wastewater drain line. Captures fats, oils, and grease (FOG) from sinks, dishwashers, and floor drains before they enter the municipal sewer system. Prevents sewer blockages and fines from the water authority.
Regulated by: City/County Water Authority
Hood Cleaning
The cleaning of the kitchen exhaust system — hood canopy, grease filters, plenum, ductwork, and rooftop exhaust fan. Removes grease vapor deposits that accumulate as a fire hazard. Required by NFPA 96 and enforced by fire and health inspectors.
Regulated by: Fire Marshal + County Health

Two Different Types of Grease

The easiest way to understand why these are separate systems is to follow the grease from where it is produced.

Liquid FOG (Fats, Oils & Grease)
Grease Trap
Produced during cooking → goes into food scraps, pots, pans, and rinse water → flows down the drain → intercepted by the grease trap before it reaches the sewer
Airborne Grease Vapor
Hood Cleaning
Produced during cooking → rises as vapor and smoke → enters the exhaust hood → condenses and deposits onto hood surfaces, ductwork interior, and exhaust fan → accumulates as flammable grease over time

Separate Compliance Requirements

Grease traps and hood cleaning are regulated by entirely different agencies. Compliance with one does not affect the other — you can be current on your grease trap and still receive a fire citation for an uncleaned hood.

Grease Trap
  • Regulated by the City of San Diego Metropolitan Wastewater Dept. and County sewer authority
  • Pumped by a licensed grease trap service company
  • Service records required — regulators may request manifests showing proper disposal
  • Violations result in fines from the water authority, not from fire or health inspectors
Hood Cleaning
  • Regulated by San Diego Fire-Rescue (NFPA 96) and County Environmental Health
  • Cleaned by IKECA-certified hood cleaning technicians
  • Service certificate and NFPA 96 sticker required as compliance documentation
  • Violations result in fire citations, health grade deductions, or closure orders

Grease Trap Basics for San Diego Operators

Most full-service restaurants in San Diego are required to have a grease trap or grease interceptor. The specific requirements depend on your discharge volume and the city or county sewer authority that serves your location.

  • Pumping frequencyTypically every 1–3 months depending on interceptor size and your operation's grease output. The standard rule is to pump when the trap is 25% full of grease and solids.
  • Who does itA licensed grease trap service company. They pump the contents, clean the trap, and provide a waste manifest documenting proper disposal at an approved facility.
  • Records requiredKeep service manifests on file. The City of San Diego's FOG (Fats, Oils, Grease) Program may request these during inspections.
  • Signs you are overdueSlow drains, sewer odors in the kitchen, or visible grease in floor drains are signs the trap may be full or failing.

Hood Cleaning Basics

Professional hood cleaning removes accumulated grease from the entire kitchen exhaust path — from the cooking surface through the ductwork and out the rooftop exhaust fan. NFPA 96 sets minimum cleaning frequencies based on your cooking type and volume.

  • MonthlySolid fuel cooking (wood, charcoal), high-volume operations, 24-hour restaurants
  • QuarterlyMost full-service San Diego restaurants — moderate cooking volume, gas or electric equipment
  • Semi-annuallyLow-volume or seasonal operations — senior centers, churches, cafeterias with limited service hours

Do You Need Both?

For almost all full-service restaurants in San Diego: yes. Both are required by separate regulatory bodies, and compliance with one does not satisfy the other.

Quick Reference

Do I need hood cleaning?
Yes, if you operate any commercial cooking equipment under an exhaust hood.
Do I need a grease trap?
Yes for most full-service restaurants. Confirm requirements with your local sewer authority.
Does cleaning my hood satisfy grease trap requirements?
No. They address different grease streams and are regulated by different agencies.
Does pumping my grease trap satisfy NFPA 96?
No. Hood cleaning must still be performed on the required schedule.

Handle the Hood Cleaning Side

Core Hood Cleaning handles the NFPA 96 side of your compliance — certified cleaning with full documentation. Book a site assessment and we will confirm the right frequency for your operation.

Schedule a Cleaning📞 (858) 361-2570

Frequently Asked Questions

What is the difference between a grease trap and hood cleaning?

A grease trap captures liquid fats, oils, and grease from drains before they reach the sewer. Hood cleaning removes grease vapor deposits from the kitchen exhaust system — the hood, ductwork, and rooftop fan. They address different grease streams, are regulated by different agencies, and have completely separate compliance requirements.

Do most San Diego restaurants need both a grease trap and regular hood cleaning?

Yes. Most full-service restaurants in San Diego are required to maintain both. Grease trap pumping is regulated by the City's wastewater authority. Hood cleaning is required by NFPA 96 and enforced by San Diego Fire-Rescue and County Environmental Health.

How often does a grease trap need to be pumped in San Diego?

Pumping frequency depends on interceptor capacity and your operation's grease output. The general rule is to pump when the trap is 25% full of grease. Many San Diego restaurants pump every 1–3 months.

What happens if I neglect my grease trap?

A full grease trap allows FOG to pass into the municipal sewer, causing blockages. The City of San Diego can issue fines and require corrective action. Repeated violations result in significant penalties.

What happens if I neglect hood cleaning?

Grease accumulates in the exhaust system, creating a direct fire hazard. Non-compliance with NFPA 96 also puts your fire permit, insurance coverage, and health grade at risk.

Can the same company do both grease trap pumping and hood cleaning?

Some companies offer both, but they require different equipment and certifications. Grease trap pumping is a licensed waste hauling service. Hood cleaning requires IKECA-certified technicians. Evaluate each service on its own merits.

Which is more urgent: a dirty grease trap or a dirty hood?

Both are serious compliance risks on different timelines. A full trap may cause a sewer backup within days. A dirty hood builds fire risk over weeks. Both should be maintained on schedule — neglecting either creates compounding risk and potential violations from different agencies simultaneously.