Kitchen Hood and Duct Cleaning: Safety Precautions

Cleaning a kitchen exhaust system means working with old grease, strong chemicals, electric motors and, often, heights. This guide explains what a safe job looks like, what to prepare as the kitchen owner and what staff should never do. For the daily and weekly routine, see our guide on how to clean a commercial kitchen hood.

Why does safety matter in exhaust cleaning?

Grease in an exhaust system is fuel. The U.S. Fire Administration found that cooking materials such as grease and oil were the items most often first ignited in restaurant fires. Cleaning removes that fuel, but the work has its own risks: caustic degreasers, hot surfaces, water near electrical parts, and ladders or roofs.

What should a safe cleaning crew do?

• Isolate the power to the exhaust fan and any ESP unit before opening them. NFPA 96 says electrical switches that could be turned on by accident must be secured in the off position before cleaning starts
• Keep the fire suppression system in service. Under NFPA 96, no part of it should be left disabled, and cleaning agents should be kept off its fusible links and detectors
• Avoid flammable solvents and flammable cleaning aids, which NFPA 96 rules out
• Cover or protect appliances and electrical equipment, and keep water away from motors, control panels and ESP units
• Wear protective equipment: coveralls, gloves, eye protection and, where something could fall, a hard hat
• Use proper access equipment for ceiling voids and roofs, and never climb onto cooking equipment
• Contain wash water and grease waste and dispose of it properly instead of letting it run into drains that are not meant for it

NFPA 96 is a U.S. standard, and its details change between editions. Your building manager and the authority that inspects your premises may set their own rules, so check what applies to you.

What should you do before the crew arrives?

1. Finish service, switch off all cooking equipment and let it cool
2. Clear the area around the hood and under the duct access panels
3. Show the crew where the gas shut-off, the electrical isolators and the fire suppression system are
4. Arrange access to the roof or ceiling void, and any keys or building permissions
5. Tell staff and neighbouring tenants about the work, the noise and any water
6. Give the crew your last cleaning report, if you have one

What should staff never do?

• Clean the hood while cooking equipment is on or still hot
• Use water jets or sprays near fan motors, control panels or ESP units
• Mix cleaning chemicals
• Open duct access panels or fan housings
• Climb onto cooking equipment to reach the canopy
• Touch or move the fire suppression nozzles or links

Staff can wash accessible filters by following the maker's instructions. The duct and the fan are professional work.

What should you ask a cleaning company about safety?

• How do you isolate the power to the fan and the ESP unit?
• How do you protect the fire suppression system?
• How do you protect appliances and electrical equipment?
• What happens to the wash water and the grease waste?
• Can you work after we close?
• Do I get a written report with before and after photos?

How does HoodEx work around your kitchen?

HoodEx works day and night shifts, so a cleaning can be arranged after your kitchen closes. Our technicians work in protective coveralls and hard hats, as you can see in our gallery. We inspect your system first, and every job ends with a company-attested report that includes before and after photos and recommendations.

Ready to plan a cleaning? Contact HoodEx and we will arrange an inspection.

Frequently asked questions