Turbo Chef Technologies Tornado 2 manual Exceptions

EXHAUST SYSTEMS

Page 7.1

EXHAUST SYSTEMS

air from the exhaust outlet discharges away from such locations.

506.4Ducts serving Type II hoods. Single or combined Type II exhaust systems for food-processing operations shall be independent of all other exhaust systems. Commercial kitchen exhaust systems serving Type II hoods shall comply with Sec- tions 506.4.1 and 506.4.2.

506.4.1Type II exhaust outlets. Exhaust outlets for ducts serving Type II hoods shall comply with Sections 401.4 and

401.4.2.Such outlets shall be protected against local weather conditions and shall meet the provisions for exte- rior wall opening protectives in accordance with the Inter- national Building Code.

506.4.2Ducts. Ducts and plenums serving Type II hoods shall be constructed of rigid metallic materials. Duct con- struction, installation, bracing and supports shall comply with Chapter 6. Ducts subject to positive pressure and ducts conveying moisture-laden or waste-heat-Iaden air shall be constructed, joined and sealed in an approved manner.

506.5Exhaust equipment. Exhaust equipment, including fans and grease reservoirs, shall comply with Sections 506.5.1 through 506.5.5 and shall be of an approved design or shall be listed for the application.

506.5.1}:xhaust fans. Exhaust fan housings serving a Type I hood shall be constructed as required for grease ducts in accordance with Section 506.3.1.1.

Exception: Fans listed and labeled in accordance with UI-I762.

506.5.1.1Fan motor. Exhaust fan motors shall be located outside of the exhaust airstream.

506.5.2Exhaust fan discharge. Exhaust fans shall be posi- tioned so that the discharge will not impinge on the roof, other equipment or appliances or parts of the structure. A vertical discharge fan shall be manufactured with an approved drain outlet at the lowest point of the housing to permit drainage of grease to an approved grease reservoir.

506.5.3Exhaust fan mounting. An upblast fan shall be hinged and supplied with a flexible weatherproof electrical cable to permit inspection and cleaning. The ductwork shall extend a minimum of 18 inches (457 mm) above the roof surface.

506.5.4Clearances. Exhaust equipment serving a Type I hood shall have a clearance to combustible construction of not less than 18 inches (457 mm).

Exception: Factory-built exhaust equipment installed in accordance with Section 304.1 and listed for a l,~sser

clearance. '

506.5.5Termination location. The outlet of exhaust equip- ment serving Type I hoods shall be in accordance with Sec-

Ition 506.3.12.

Exception: The minimum horizontal distance between vertical discharge fans and parapet-type building struc- tures shall be 2 feet (610 mm) provided that such struc-

tures are not higher than the top of the fan discharge opening.

SECTION 507

COMMERCIAL KITCHEN HOODS

507.1General. Commercial kitchen exhaust hoods shall com- ply with the requirements of this section. Hoods shall be Type I

or Type II and shall be designed to capture and confine cooking I vapors and residues. Commercial kitchen exhaust hood sys- tems shall operate during the cooking operation.

Exceptions:

1.Factory-built commercial exhaust hoods which are tested in accordance with UL 710, listed, labeled and installed in accordance with Section 304.1 shall not be required to comply with Sections 507.4, 507.7, 507.11,507.12,507.13,507.14 and 507.15.

2.Factory-built commercial cooking recirculating sys- tems which are tested in accordance with UL 710B, I listed, labeled and installed in accordance with Sec- tion 304.1 shall not be required to comply with Sec- tions 507.4,507.5,507.7,507.12,507.13,507.14 and 507.15.

3.Net exhaust volumes for hoods shall be permitted to be reduced during no-load cooking conditions, where engineered or listed multispeed or variable-speed controls automatically operate the exhaust system to maintain capture and removal of cooking effluents as required by this section.

507.2Where required. A Type I or Type II hood shall be installed at or above all commercial cooking appliances in accordance with Sections 507.2.1 and 507.2.2. Where any cooking appliance under a single hood requires a Type I hood, a Type I hood shall be installed. Where a Type II hood is required, a Type I or Type II hood shall be installed.

.. 507.2.1 Type I hoods. Type I hoods shall be installed where cooking appliances produce grease or smoke, such as occurs with griddles, fryers, broilers, ovens, ranges and wok ranges.

507.2.1.1Operation. Type I hood systems shall be designed and installed to automatically activate the exhaust fan whenever cooking operations occur. The activation of the exhaust fan shall occur through an inter- lock with the cooking appliances, by means of heat sen- sors or by means of other approved methods.

507.2.2.Type II hoods. Type II hoods shall be installed where cooking or dishwashing appliances produce heat, steam, or products of combustion and do not produce grease or smoke, such as steamers, kettles, pasta cookers and dishwashing machines.

Exceptions:

1.Under-counter-type commercial dishwashing machines.

2.A Type II hood is not required for dishwashers and potwashers that are provided with heat and water

vapor exhaust systems that are supplied by the appliance manufacturer and are installed in accor- dance with the manufacturer's instructions.

.... 3. A single light-duty electric convection, bread,

retherm or microwave oven. The additional heat and moisture loads generated by such appliances shall be accounted for in the design of the HVAC system.

4.A Type II hood is not required for the following electrically heated appliances: toasters, steam tables, popcorn poppers, hot dog cookers, coffee makers, rice cookers, egg cookers, holding/warm- ing ovens. The additional heat and moisture loads generated by such appliances shall be accounted for in the design of the HVAC system.

507.2.3Domestic cooking appliances used for commer- cial purposes. Domestic cooking appliances utilized for commercial purposes shall be provided with Type I or Type II hoods as required for the type of appliances and processes in accordance with Sections 507.2, 507.2.1 and 507.2.2.

507.2.4Extra-heavy-duty.Type I hoods for use over extra-heavy-duty cooking appliances shall not cover other appliances that require fire extinguishing equipment and such hoods shall discharge to an exhaust system that is inde- pendent of other exhaust systems.

507.3Fuel-burning appliances. Where vented fuel-burning appliances are located in the same room or space as the hood, provisions shall be made to prevent the hood system from inter- fering with normal operation of the appliance vents.

507.4Type I materials. Type I hoods shall be constructed of steel not less than 0.043 inch (1.09 mm) (No. 18 MSG) in thick- ness, or stainless steel not less than 0.037 inch (0.94 mm) (No. 20 MSG) in thickness.

507.5Type II hood materials. Type II hoods shall be con- structed of steel not less than 0.030 inch (0.76 mm) (No. 22 Gage) in thickness, stainless steel not less than 0.024 inch (0.61

mm)(No. 24 Gage) in thickness, copper sheets weighing not less than 24 ounces per square foot (7.3 kg/m2), or of other approved material and gage.

507.6Supports. Type I hoods shall be secured in place by non- combustible supports. All Type I and Type II hood supports

shall be adequate for the applied load of the hood, the unsup- ported ductwork, the effluent loading, and the possible weight

of personnel working in or on the hood.

507.7Hood joints, seams and penetrations. Hood joints, seams and penetrations shall comply with Sections 507.7.1 and

507.7.1Type I hoods. External hood joints, seams and pen- etrations for Type I hoods shall be made with a continuous external liquid-tight weld or braze to the lowest outermost perimeter of the hood. Internal hood joints, seams, penetra- tions, filter support frames, and other appendages attached

inside the hood shall not be required to be welded or brazed but shall be otherwise sealed to be grease tight.

Exceptions:

1.Penetrations shall not be required to be welded or brazed where sealed by devices that are listed for the application.

2.Internal welding or brazing of seams, joints, and penetrations of the hood shall not be prohibited provided that the joint is formed smooth or ground so as to not trap grease, and is readily cleanable.

507.7.2Type II hoods. Joints, seams and penetrations for Type II hoods shall be constructed as set forth in Chapter 6, shall be sealed on the interior of the hood and shall provide a smooth surface that is readily cleanable and water tight.

507.8Cleaning and grease gutters. A hood shall be designed to provide for thorough cleaning of the entire hood. Grease gut- ters shall drain to an approved collection receptacle that is fab- ricated, designed and installed to allow access for cleaning.

507.9Clearances for Type I hood. A Type I hood shall be installed with a clearance to combustibles of not less than 18 inches (457 mm).

Exception: Clearance shall not be required from gypsum wallboard attached to noncombustible structures provided that a smooth, cleanable, nonabsorbent and noncombustible material is installed between the h90d and the gypsum wall- board over an area extending not less than 18 inches (457

mm)in all directions from the hood.

507.10Hoods penetrating a ceiling. Type I hoods or portions thereof penetrating a ceiling, wall or furred space shall comply with all the requirements of Section 506.3.10.

507.11Grease filters. Type I hoods shall be equipped with listed grease filters designed for the specific purpose. Grease-collecting equipment shall be provided with access for cleaning. The lowest edge of a grease filter located above the cooking surface shall be not less than the height specified in Table 507.11.

TABLE 507.11

MINIMUM DISTANCE BETWEEN THE LOWEST EDGE OF A GREASE FILTER AND THE COOKING SURFACE OR THE HEATING SURFACE

TYPE OF COOKING	HEIGHT ABOVE COOKING
APPLIANCES	SURFACE (feet)
Without exposed flame	0.5
Exposed flame and burners	2
Exposed charcoal and charbroil type	3.5

For SI: 1 foot =304.8 mm.

507.11.1Criteria. Filters shall be of such size, type and arrangement as will permit the required quantity of air to pass through such units at rates not exceeding those for which the filter or unit was designed or' approved. Filter units shall be installed in frames or holders so as to be readily removable without the use of separate tools, unless

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