4th year Flashcards
What is the purpose of a properly commercial kitchen systems ?
Safe and Better working condition for all those involved
The commercial kitchen exhaust system must contain the product of the process to where ?
To the fan that delivers the products outdoors
List seven pieces of equipment or components that you will find on a typical commercial kitchen exhaust system
1) Exhaust hood or canopy 2) integral grease filtration 3) fire suppression system 4) exhaust duct system 5) exhaust fan 6) make-up air (MUA) unit 7) control interlock device
What is the function of a kitchen canopy or hood ?
To capture the plume of heated air rising from the hot cooking surface
List six things that could exist within a commercial kitchen effluent’’.
Grease particles ,Grease vapour,Heat ,Odour,Moisture and Volatile organic compounds
What are the 3 things that are captured and contained from the effluent in a commercial kitchen exhaust system?
extraction baffles, filters and water mist systems
What are seven considerations that should be considered when selecting a hood style in commercial kitchen?
Type of grill , deep fryer, steam kettle, open or closed flame ranges, ovens or dishwashing equipment and other similar heat and steam producing equipment
What are the kitchen exhaust minimum air flow rates designed to do?
To Contain and exhaust undesirable cooking products generated by the appliances
What are the two main categories of commercial kitchen exhaust hoods?
Type 1 ventilation Hood and Type 2 ventilations Hood
What are type1 Hoods designed to handle in regards to a commercial kitchen?
Are designed to handle heat and grease laden effluent
What are two components that must be included within a type1Hood?
Integrated filtration components and fire suppression components
What are two things are necessary in regards to. Construction of a type?
They must be continuously welded and liquid tight
What are two board categories of type1 Hoods?
Standard and Listed
Standard type1 Hoods must meet the requirements set out by 3 standards, what are they?
1) Alberta Building Codes (ABC) 2) National Fire Protection Association (NFPA) 3) No-96 Ventilation Control and Fire Protection of Commercial Cooking Operations, UL-300 fire extinguishing system for protection of commercial cooking or ULC/ord-c1254.6 fire testing of restaurant cooking area fire extinguishing system units
What do listed type1 Hoods carry in regards to certification
ULC listing label
What do type II Hoods collect that differs from a type I Hood?
Steam vapour,low heat and odours
What are two basic styles or type of Hoods?
Canopy Hoods and Non-Canopy Hoods
List four sub-styles or types of Hoods
Island canopy,Wall canopy,Corner canopy and Slop canopy
How many sides of an Island canopy are exposed to draw air in?
Four sides are exposed
How many sides of a wall canopy are exposed to draw air in ?
Three sides are exposed
How many sides of a corner canopy are exposed to draw air in ?
Two sides are exposed
What would a slot canopy be used in place of ?
a large canopy Hood
What is one advantage of using a slot canopy ?
can exhaust effluent at lower CFM
What are two disadvantages of using a slot canopy?
1) A larger maintenance times are required to wash the canopy and filter 2) complexity to fabricate and meet the requirements of standards
List two basic styles of non-canopy Hoods.
Backshelf (or Passover) and Eyebrow
How are pre-manufactured non-canopy Hoods sized ?
According to the manufacturer’s specifications
Where are back shelf hoods typically installed?
They’re designed to be installed closer to the cooking area
Where are back shelf hoods installed in relation to the front edge of the cooking surface ?
Back from the front edge of the cooking surface
Where eyebrow hoods normally installed?
oven type equipment
What are grease removal systems designed to reduce?
the amount of combustible matter in the exhaust air
Describe the process of grease removal through these devices.
collect the airborne particles and concentrating them so they may be disposed of a later time
List 4 items that could be part of the grease removal system.
Filters,Baffles,Air washers and Ultraviolet technology
What happens to the grease that is collected through the grease removal system ?
collected in grease drip treys where it can be later discarded
What 4 codes must the grease removal system meet when installed ?
NFPA, ABC, manufacturer’s instructions and the authority having jurisdiction
What do fire suppression systems ensure?
If there’s a flare-up fire it is suppressed before any heat damage can occur
What happens when the sensor inside the hood detects a flare-up or fire ?
Turn on chemicals fire suppression or containment agents directly on the fire, extinguishing it entirely
What must be used in a hood that is designed to extract grease?
ULC rated fire suppression system
Give a brief definition to describe the exhaust duct system.
The means of containing the exhausted air until it leaves the structure
What shape of duct is generally used in a commercial kitchen exhaust system?
Generally square or rectangular
In which direction should commercial kitchen exhausts be preferably installed?
It’s preferred to go vertical with as few direction changes or transitions as possible.
Who must approve commercial kitchen exhaust ducts to be installed?
ULC rated or local jurisdiction
Who must approve exhaust fans and motors used in a commercial kitchen exhaust system?
ULC/CSA approved.
In regards to operations, what must a fan used in a commercial kitchen exhaust system be rated for?
continuous operation.
What size exhaust fan must be used in a commercial kitchen exhaust system?
Size to maintain air velocity in the hood over the cooking area to properly entrain a grease particles and Vapor’s .
What is the minimum air velocity through the duct according to NFPA?
500 fpm
How do we determine the volume of air that needs to be exhausted by the fan in a commercial kitchen exhaust system?
Is determined by the hood type.
How much make-up air is required in a commercial kitchen?
Air must be provided in approximately equal amounts to replace the kitchen air being exhausted.
Where do we typically get air for make-up?
Outside air
What are the three ways that make-up air can be delivered to the kitchen?
- Through one supply type
- Transfer air
3.multiple sources
What type of pressure is desirable within the kitchen with respect to the dinning room?
A slight negative pressure is desirable.
With the pressure identified in the previous question, why is this desirable?
To keep odours out of the dinning area.
What should be taken into consideration to avoid uncomfortable draft conditions when installing a make-up system?
Location of the air inlets
How’s the air tempered in a make-up air system?
By the use of a separate control
What would happen to the designed exhaust volume if there was no make-up air?
The exhaust fan would not be able to exhaust the design volume
what would be the result of having a large negative pressure within a commercial kitchen?
. Negative pressure would cause improper venting of water heaters, space heaters or other individually vented gas appliances in the building.
What does a control interlock-panel system ensure in a commercial kitchen?
To ensure that the makeup air is supplied when the kitchen exhaust fan is turned on and vice versa
What are 2 things that interlocks prevent in a commercial kitchen/restaurant?
Prevent kitchen fumes from entering the dinning area as well as ensure satisfactory venting of other gas appliances.
What two publications do we generally adopt local codes in regards to a commercial kitchen exhaust system?
The Alberta building code or NFPA standard No-96
In most major cities, who writes and publishes local codes?
By local building officials.
What are local codes frequently based on?
National codes
Who do planners and designers need to consult prior to designing a commercial kitchen ventilation system?
local authority having jurisdiction
What are the two scenarios that an architect or engineer would need to pre-approve a commercial kitchen exhaust system on plans and specifications with an approval stamp?
More than three stories in building height and if the floor area of the combined kitchen and dining area is greater than 3200 sq ft or 300m*
What 2 codes need to be followed when designing and constructing a commercial kitchen exhaust canopy?
Alberta Building Codes and NFPA-96
How much overhang must a commercial kitchen canopy have in regards to the cooking equipment?
At least 6” overhang
What type of seam and joints need to be on a kitchen exhaust canopy?
Continuous liquid tight welds.
What gauge of mild steel and stainless steel can be used in the construction and installation of a commercial kitchen canopy?
1) 18-gauge ms or 20-gauge SS.
What type of fitting should be used on the top of a commercial kitchen exhaust canopy?
Transition
At what length of the commercial kitchen exhaust canopy is it desirable to have two take-offs on the top for discharge?
10 ft
What type of material must be used for any exposed canopies , hoods or duct used in a commercial kitchen?
Stainless steel
What is the best scenario for routing a commercial kitchen exhaust duct from a canopy to the roof?
vertically to the roof with minimal offsets and turns to minimize pressure losses.
What gauge of mild steel and stainless steel can be used in the construction and of commercial kitchen exhaust duct?
At least 16 gauge mild steel or 18 gauge stainless steel.
What types of seams and joints must be on a commercial kitchen duct?
Continuous weld.
Where to all commercial kitchen exhaust ducts need to lead directly to?
All ducts should lead directly outdoors or to the exterior of the building.
What other building exhaust or ventilation system[s] can I attach a commercial kitchen exhaust duct too?
None, duct systems should not be interconnected with any other building ventilation or exhaust.
If I have a multi floor building can I attach multi-floor exhaust systems to one riser?
No
For the purpose of inspection and cleaning, where can I install access doors on a commercial kitchen exhaust duct?
Sides and Top
What size access doors need to be installed on a commercial kitchen exhaust duct?
20”/ 20”
How far from the edges must I leave a space when installing an access door on a commercial kitchen exhaust duct?
1 1/2
How far apart should I install access doors that are not 20”x20”?
12 foot intervals.
What types of materials must the access doors be constructed of?
same material thickness as the duct
What type of fasteners shall be used on a commercial kitchen exhaust duct?
Carbon steel or stainless steel
Is it acceptable for fasteners such as screws and bolts to penetrate the duct walls?
No, should not penetrate duct walls.
How much extra weight do I need to allow for at any point in the duct system if any cross-sectional are exceeds 24”?
800 pounds.
Can commercial kitchen exhaust ducts pass through fire walls or fire partitions?
No, ducts should not pass through fire walls or fire partitions.
How much clearance must a commercial kitchen exhaust duct have to combustibles.
A clearance to the duct of not less than 18 inches.
How can we reduce clearances from combustibles when installing a commercial kitchen exhaust duct?
Use of materials or products suitable to the authority having jurisdiction.
If we install a fire rated shaft for the commercial kitchen exhaust duct, what is the fire resistance rating for buildings less than four stories tall?
1 hour fire rating
If we install a fire rated shaft for the commercial kitchen exhaust duct, what is the fire resistance rating for buildings more than four stories tall?
2 hour fire rating
How far away from adjacent buildings, air intakes or property lines must a commercial kitchen exhaust duct terminate outside?
Should terminate with a minimum of 10 feet.
How far from the roof surface must the outlet for a fan discharge be?
At least 40 inches.
What can be done if the clearance cannot be maintained from the roof from previous question?
Use a metal pan with a minimum 1.00” lip at the edges to catch residue.
What is the minimum distance from the cooking surface we can install the grease removal device?
18 inches.
What is the minimum distance from the cooking surface that uses charcoal or char broilers can we install a grease removal device?
Minimum vertical distance of 4 feet shall be maintained between the lower edge of the grease removal device and the cooking surface.
What type of construction can we use for grease filters in a commercial kitchen?
Listed (approved) Constructed of steel or equivalent material,must be rigid
How shall grease filters be arranged within the canopy or hood?
So that all exhaust air passes trough the filter.
At what angle must we install grease filters within canopy or hood?
not less than 45 degrees from horizontal.
What must be install at the bottom edge of the grease filters in a canopy or hood?
grease drip tray .
What is the maximum storage capacity of the grease collector?
Capacity not to exceed 1 US gallon.
What needs to be done to winter air that is brought in for make-up air in a commercial kitchen?
Must be preheated to maintain indoor design temperatures .
What are commercial grease filters designed to do?
to capture the highly combustible grease from the effluent and direct it to a collection system.
What can happen if we do not use grease filters in a commercial kitchen canopy or hood?
build up of grease in the duct and on the fan blades ,motor could cause a flash fire
What is the result of grease deposits on a commercial kitchen exhaust fan wheel?
Could unbalance the wheel assembly and wear out the bearing and also reduce airflow
What is the result of grease deposits on a commercial kitchen exhaust fan motor?
overheating, which will then create an additional fire hazard.
Lis three types of grease filters and extractors.
A.baffle filter
B.water wash filter
C. Exhaust hood with us technology
What type of force extracts grease through a baffle type grease filter?
Centrifugal forces
When using up technology what is significantly reduced in the air steam?
Reduces odours
Typically, what is the optimum operating velocity of air through a baffle type grease filter?
Velocity grease filter is
150 fpm to 300 fpm.
Where can I obtain more accurate optimum operating velocity of air through a baffle type grease filter?
The manufacturer will give details on their optimum operating velocity as well as installation instructions.
What type of rating needs to be on the baffle type grease filter?
ULC rated
