Commercial Kitchen Exhaust Systems

Question 1

What are the two types of hoods?

Answer 1

Type 1
Type 2

Question 2

What are type 1 hoods designed for?

Answer 2

Designed to handle heat and grease.

Question 3

True or false? Type 1 hoods include fire suppression systems and must be liquid tight?

Answer 3

True

Question 4

Two categories of type 1 hoods?

Answer 4

Standard

Listed

Question 5

True or false? Standard type 1 hoods have no set requirements?

Answer 5

False. They must be constructed to meet the requirements set out by ABC, NFPA and must conform to UL-300

Question 6

What certification do listed type 1 hoods carry?

Answer 6

ULC

Question 7

What are type 2 hoods used for?

Answer 7

Collection of steam, vapour, low heat, and odours

Question 8

Two basic styles of hoods?

Answer 8

Canopy

Non-canopy

Question 9

Four sub styles of canopy hoods?

Answer 9

Island
Wall
Corner
Slot

Question 10

Two basic styles of non-canopy hoods?

Answer 10

Backshelf (or Passover)
Eyebrow

Question 11

True or false. Backself hoods are designed to be installed close to the cooking area?

Answer 11

True

Question 12

What type of equipment are eyebrow hoods designed to be installed over?

Answer 12

Oven type equipment. They exhaust effluent from the front of equipment

Question 13

Within a grass removal system there are several grease removal devices. What are they?

Answer 13

Filters
Baffles
Air washers
Ultraviolet technology

Question 14

Hoods used to extract grease must be protected with what?

Answer 14

A ULC rated fire suppression system

Question 15

What two things happen when a fire suppression system detects a fire

Answer 15

Energy sources shut down and activate system foaming agent

Question 16

True or false? Exhaust fans and motors shall be ULC/CSA approved and rated to run only for operation hours of the restaurant?

Answer 16

False. They must be rated for continuous operation

Question 17

The NFPA 96 2010 edition requires a minimum air velocity through the duct be maintained at a minimum air velocity. What is it?

Answer 17

500 FPM

Question 18

What does kitchen exhaust effluent contain?

Answer 18

Grease particles, grease vapour, heat, odour, moisture, and volatile compounds.

Question 19

Why is a slight negative pressure in the kitchen desirable

Answer 19

It keeps kitchen odours out of the dining room

Question 20

What does a control interlock-panel system do?

Answer 20

It ensures that the make up air is supplied when the exhaust fan is turned on

Question 21

How much bigger should a canopy be than the equipment it is ventilating?

Answer 21

6” bigger on all sides

Question 22

If extra mechanical field joints are permitted what factors must they meet?

Answer 22

They must me exposed and accessible

Question 23

True or false. If a hood length exceeds 10’ then it is desirable to have two discharge ducts from the top of the hood to join the main exhaust duct

Answer 23

True

Question 24

How should grease ducts be routed?

Answer 24

Vertically to the roof with minimal offsets and turns. Sidewall venting is possible but must adhere to local codes

Question 25

How much clearance to combustible materials must a duct have where it passes through partitions or walls?

Answer 25

18”

Question 26

Duct systems should terminate how far from adjacent buildings, air intakes and property lines?

Answer 26

10’

Question 27

The distance between grease removal devices and cooking surfaces shall be as great as possible but no less than how many inches?

Answer 27

18”

Question 28

What is the minimum vertical distance for grease removal devices from a charcoal type broiler

Answer 28

4’

Question 29

What is the minimum angle a grease filter can be installed at?

Answer 29

45 degrees

Question 30

How do baffle filters remove grease from the airflow?

Answer 30

Centrifugal force

Question 31

When calculating how many filters are required for a hood. What must be done if the number calculated has a decimal?

Answer 31

It must be rounded up to the next whole number (eg 2.3 rounds up to 3)

Question 32

3 types of exhaust fans?

Answer 32

Impeller or inline fans Up-blast fans Blower or utility fans

Question 33

Impeller fans use blades similar to what?

Answer 33

Airplane propeller

Question 34

Up-blast fans use what kind of blades?

Answer 34

Centrifugal backward inclined fan wheel

Question 35

Blower or utility fans offer a variety of discharge positions and are often called what?

Answer 35

Squirrel cage fans

Question 36

What type of fan is generally more efficient than the others?

Answer 36

Blower