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GREASE HOOD EXHAUST SYSTEM CLEANING
Kitchen exhaust cleaning is required by law for virtually every commercial cooking
establishment in the United States. Restaurants, hospitals, hotels, employee cafeterias
and other food-service locations have a "hood" and ductwork over the stove to exhaust
smoke, steam, and fumes out of the building. These exhaust gases leave a residue on the
inside of the ductwork. This is usually a grease residue of some sort, depending on the type
of cooking. Char broilers commonly leave heavy black grease. Chinese cooking normally
deposits a sticky or rubbery residue.
When a charcoal or wood-burning stove is in use soot and ash residue builds up in the
ductwork. Dishwashers leave heavy lint deposits.
When the buildup of grease becomes heavy, a fire hazard exists. Approximately one of
three restaurant fire sis caused by grease. A common scenario of how a kitchen exhaust
fire starts is this:A flame flares up on the stove.
The fire contacts the filters above the stove on the kitchen hood. The filters ignite.
Since the exhaust fan is on, drawing air into the hood, through the filters, and up the
duct, the flame on the filters is pulled into the duct.If significant grease residue
exists on the duct interior, this can act as a fuel and the fire spreads up the duct, perhaps
all the way into the fan. We have seen fire climb up a five-story duct to the fan on the roof
and burn up the fan. Modern duct construction is designed to hopefully withstand such
duct fires. The duct seams are welded to prevent grease or fire from leaking out and the
shafts around the duct are made of fire- resistive materials. However, older buildings are
still at risk, and even in modern ones the fire may leak out or could come out onto the
roof via the fan. When an exhaust system is cleaned regularly, however, the chances of
a duct fire are extremely remote.
METHODS OF CLEANING
There are two primary methods of cleaning kitchen exhaust ductwork:
Scraping - The primary method used is scraping. This is the more economical method
and is extremely effective when done thoroughly. We know of no duct fires that have
occurred because of using this method (unless it was done poorly). Scraping of duct
systems complies with the Uniform Fire Code that is the governing fire code of the state of
Massaussette. The most common method for kitchen exhausts is the scraping method.
Pressure Washing or Steam Cleaning - The alternative to scraping is pressure washing
or steam-cleaning. This is a more costly and time-consuming technique, since it requires
considerable prep work to control wastewater and more expensive equipment is involved.
However,this method will clean ductwork down to "bare metal," which is the
recommendation of the National Fire Protection Association (NFPA) as spelled out in NFPA
Standard 96. We frequently do pressure washing of kitchen exhausts as well as scraping.
This is done for a variety of reasons. Sometimes the ductwork may be inaccessible for
scraping or the client simply wants to take the extra precautionary step of having it cleaned
to "bare metal".
WHEN CONTRACTING FOR CLEANING SERVICES
It is important to ensure you get a complete cleaning of your entire system.
Some contractors offer a "hood cleaning" service which does not include the
ductwork or rooftop fan. While such services may keep the interior of the kitchen
looking sharp, they do little to secure fire safety and reduce health threats.
Only a complete cleaning of the system-from the hood in the kitchen to the
fan on the roof-will reduce the risk of kitchen fires and ensure compliance
with fire regulations.
ALL PROFESSIONAL KITCHEN EXHAUST SYSTEM CLEANING
All Professional kitchen exhaust cleaning companies should supply you with a
"Certificate of Performance." NFPA codes require this Certificate to be posted
near the hood, much like the sticker tag on your fire system. The Certificate
should state the date the system was cleaned and expiration date, as well as
noting if there are inaccessible areas in the system.
We will work overnight, so that your restaurant may remain open during its usual business hours.
Vincent Exhaust Services, Inc. crews always mop up and thoroughly clean all work areas when the
project is completed, so you'll be ready to cook. We always leave a hood sticker which indicates the
date of cleaning and the date we recommend your next cleaning in order to satisfy fire and insurance
officials. Our office will call you to schedule each cleaning at your convenience.
ENVIROMENTAL HEALTH
The cleanliness of the kitchen exhaust system is one of the assessment criteria
in the grading system for food outlets. Enforcement action may also be
taken against the licensees of food outlets who fail to keep their kitchen exhaust
system clean.
BENEFITS OF CLEANING
Reduced risks of kitchen fires
Enhanced working environment for kitchen staff
Improved ventilation for smoke and odor removal
Lower insurance premiums offered by some insurance companies
Compliance with local and national fire and health codes.
