Makeup air, testing, maintenance and auxiliary equipment

Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:

• CMC § 910.4.3.1 High relevance — show source text

  910.4.3.1 Makeup air. Makeup air openings shall be provided within 6 feet (1829 mm) of the floor level. Operation of makeup air openings shall be manual or automatic. The minimum gross area of makeup air inlets shall be 8 square feet per 1,000 cubic feet per minute (0.74 m [2] per 0.4719 m [3] /s) of smoke exhaust.

  910.4.4 Activation. The mechanical smoke removal system shall be activated by manual controls only.

  910.4.5 Manual control location. Manual controls shall be located where they are able to be accessed by the fire service from an exterior door of the building and separated from the remainder of the building by not less than 1-hour fire barriers constructed in accordance with Section 707 of the California Building Code or horizontal assemblies constructed in accordance with Section 711 of the California Building Code, or both.

  910.4.6 Control wiring. Wiring for operation and control of mechanical smoke removal systems shall be connected ahead of the main disconnect in accordance with Section 701.12E of the California Electrical Code and be protected against interior fire exposure to temperatures in excess of 1,000°F (538°C) for a period of not less than 15 minutes.

  910.4.7 Controls. Where building air-handling and mechanical smoke removal systems are combined or where independent building air-handling systems are provided, fans shall automatically shut down in accordance with the California Mechanical Code . The manual controls provided for the smoke removal system shall have the capability to override the automatic shutdown of fans that are part of the smoke removal system.

  910.5 Maintenance and testing. Maintenance and testing of smoke and heat vents and mechanical smoke removal systems shall be in accordance with Sections 910.5.1 and 910.5.2. A written record of inspection, testing and maintenance that includes the date, identification of personnel involved, any unsatisfactory result, corrective action taken and replaced parts shall be maintained on the premises.

  910.5.1 Smoke and heat vents. Smoke and heat vents shall be maintained in an operative condition. Inspection, testing and maintenance shall be in accordance with NFPA 204 except as follows:

  1. Mechanically operated smoke and heat vents shall be inspected annually and operationally tested not less than every 5

  years. 2. Gravity dropout smoke and heat vents shall be inspected annually. 3. Fused, damaged or painted fusible links shall be replaced.

  910.5.2 Mechanical smoke removal systems. Mechanical smoke removal systems shall be maintained in accordance with NFPA 204 and the equipment manufacturer’s instructions except as follows:

  1. Systems shall be inspected and operationally tested annually.
  2. Testing shall include the operation of all system components, controls and ancillary equipment, such as makeup air openings.
  3. A written schedule for routine maintenance and operational testing shall be established and testing shall be conducted in accordance with the schedule.

  SECTION 911—EXPLOSION CONTROL

  911.1 General. Explosion control shall be provided in the following locations:

  1. Where a structure, room or space is occupied for purposes involving explosion hazards as identified in Table 911.1.
  2. Where quantities of hazardous materials specified in Table 911.1 exceed the maximum allowable quantities in Table 5003.1.1(1).
• CMC § 90.1 High relevance — show source text

  (2) Disable mechanical cooling or reset the cooling setpoint to 90°F (32°C) or more within five minutes of the door opening. Mechanical cooling shall be permitted to remain enabled where outdoor air temperature is less than the space temperature.

  Exceptions:

  (1) Building entries with automatic closing devices.

  (2) Any space without a thermostat.

  (3) Alterations to existing buildings.

  (4) Loading docks. [ASHRAE 90.1:6.5.10]

  E 503.6 Submittals. The Authority Having Jurisdiction shall require submittal of compliance documentation and supplemental information in accordance with Section E 503.6.1 through Section E 503.6.3.

  E 503.6.1 Construction Details. Compliance documents shall show all the pertinent data and features of the building, equipment, and systems in sufficient detail

  TABLE E 503.5.13

  HOT GAS BYPASS LIMITATION

  [ASHRAE 90.1: TABLE 6.5.9]

  For SI units: 1000 British thermal units per hour = 0.293 kW

  »

  to be in accordance with Section E 503.5.11.2.2, additional performance testing shall be required to demonstrate proper capture and containment at minimum airflow. [ASHRAE 90.1:6.5.7.2.4]

  E 503.5.11.3 Laboratory Exhaust Systems. Buildings with laboratory exhaust systems having a total exhaust rate of more than 5000 ft [3] /min (2.3597 m [3] /s) shall include not less than one of the following features:

  (1) VAV laboratory exhaust and room supply systems capable of and configured to reduce exhaust and makeup airflow rates, incorporate a heat recovery system to precondition makeup air from laboratory exhaust, or both, and shall be in accordance with the following:

  A + B - ( E/M ) ≥ 50% (Equation E 503.5.11.3)

  Where:

  A = Percentage that the exhaust and makeup airflow rates are capable of being reduced from design conditions.

  B = Sensible energy recovery ratio.

  E = Exhaust airflow rate through the heat recovery device at design conditions.

  M = Makeup airflow rate of the system at design conditions.

  (2) VAV laboratory exhaust and room supply systems that are required to have minimum circulation rates to be in accordance with the codes or

  accreditation standards shall be capable of and configured to reduce zone exhaust and makeup airflow rates to the regulated minimum circulation values, or the minimum required to maintain pressurization relationship requirements. Systems serving nonregulated zones shall be capable of and configured to reduce exhaust and makeup airflow rates to 50 percent of the zone design values, or the minimum required to maintain pressurization relationship requirements.

  (3) Direct makeup (auxiliary) air supply of 75 percent or more of the exhaust airflow rate, heated not more than 2°F (1°C) below room setpoint, cooled to not less than 3°F (2°C) above room setpoint, no humidification added, and no simultaneous heating and cooling are used for dehumidification control. [ASHRAE 90.1:6.5.7.3]

  E 503.5.12 Radiant Heating Systems. Radiant heating systems shall be in accordance with Section E 503.5.12.1 through Section E 503.5.12.2.

• CMC § 511.2 High relevance — show source text

  511.2 Airflow. . . . . . . . . . . . . . . . . . . . . . 121

  511.3 Makeup Air . . . . . . . . . . . . . . . . . . 122

  511.4 Common Duct (Manifold) Systems . . . . . . . . . . . . . . . . . . . . 122

  511.5 Solid-Fuel Air Movement

  Requirements . . . . . . . . . . . . . . . . 122

  512.0 Auxiliary Equipment . . . . . . . . . . . 122

  512.1 Dampers . . . . . . . . . . . . . . . . . . . . 122

  512.2 Electrical Equipment. . . . . . . . . . . 122

  512.3 Other Equipment . . . . . . . . . . . . . 123

  512.4 Solid-Fuel Auxiliary Equipment. . . 123

  513.0 Fire-Extinguishing Equipment. . . . 123

  513.1 General. . . . . . . . . . . . . . . . . . . . . 123

  513.2 Types of Equipment . . . . . . . . . . . 123

  513.3 Simultaneous Operation . . . . . . . . 124

  513.4 Fuel and Electric Power Shutoff . . 125

  513.5 Manual Actuation . . . . . . . . . . . . . 125

  513.6 System Annunciation . . . . . . . . . . 125

  513.7 Special Design and Application . . 125

  513.8 Review and Certification. . . . . . . . 125

  513.9 Installation Requirements . . . . . . . 125

  513.10 Portable Fire Extinguishers . . . . . 125

  513.11 Maintenance . . . . . . . . . . . . . . . . . 125

  513.12 Solid-Fuel Fire-Extinguishing Equipment . . . . . . . . . . . . . . . . . . 126

  514.0 Procedures for the Use, Inspection, Testing, and Maintenance of Equipment. . . . . . 126

  514.1 Operating Procedures . . . . . . . . . 126

  514.2 Inspection, Testing and Maintenance . . . . . . . . . . . . . . . . . 126

  514.3 Inspection for Grease Buildup . . . 126

  Table 514.3 Schedule of Inspection for Grease Buildup. . . . . . . . . . . . . . . 126

  514.4 Cleaning of Exhaust Systems. . . . 126

  514.5 Cooking Equipment Maintenance . 127

  515.0 Minimum Safety Requirements for Cooking Equipment . . . . . . . . . 127

  515.1 Cooking Equipment . . . . . . . . . . . 127

  515.2 Operating Controls . . . . . . . . . . . . 128

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  TABLE OF CONTENTS

  516.0 Recirculating Systems . . . . . . . . . 128

  516.1 General Requirements . . . . . . . . . 128

  516.2 Design Restrictions. . . . . . . . . . . . 128

• CMC § 503.5.11.3 Medium relevance — show source text

  A + B - ( E/M ) ≥ 50% (Equation E 503.5.11.3)

  Where:

  A = Percentage that the exhaust and makeup airflow rates are capable of being reduced from design conditions.

  B = Sensible energy recovery ratio.

  E = Exhaust airflow rate through the heat recovery device at design conditions.

  M = Makeup airflow rate of the system at design conditions.

  (2) VAV laboratory exhaust and room supply systems that are required to have minimum circulation rates to be in accordance with the codes or

  accreditation standards shall be capable of and configured to reduce zone exhaust and makeup airflow rates to the regulated minimum circulation values, or the minimum required to maintain pressurization relationship requirements. Systems serving nonregulated zones shall be capable of and configured to reduce exhaust and makeup airflow rates to 50 percent of the zone design values, or the minimum required to maintain pressurization relationship requirements.

  (3) Direct makeup (auxiliary) air supply of 75 percent or more of the exhaust airflow rate, heated not more than 2°F (1°C) below room setpoint, cooled to not less than 3°F (2°C) above room setpoint, no humidification added, and no simultaneous heating and cooling are used for dehumidification control. [ASHRAE 90.1:6.5.7.3]

  E 503.5.12 Radiant Heating Systems. Radiant heating systems shall be in accordance with Section E 503.5.12.1 through Section E 503.5.12.2.

  E 503.5.12.1 Heating Unenclosed Spaces. Radiant heating shall be used when heating is required for unenclosed spaces.

  Exception: Loading docks equipped with air curtains. [ASHRAE 90.1:6.5.8.1]

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  APPENDIX E

  to permit a determination of compliance by the building official and to indicate compliance with the requirements of this appendix. [ASHRAE 90.1:4.2.2.1] E 503.6.2 Supplemental Information. Supplemental information necessary to verify compliance with this appendix, such as calculations, worksheets, compliance forms, vendor literature, or other data, shall be made available where required by the Authority Having Jurisdiction. [ASHRAE 90.1:4.2.2.2]

  E 503.6.3 Manuals. Operating and maintenance information shall be provided to the building owner. This information shall include, but not be limited to, the information specified in Section E 503.6.3.1, Section E 503.6.3.2, and Section E 503.6.5.2. [ASHRAE 90.1:4.2.2.3]

  E 503.6.3.1 Required Information. Construction documents shall require that an operating manual and maintenance manual be provided to the building owner. The manuals shall include, at a minimum, the following:

  (1) Submittal data stating equipment rating and selected options for each piece of equipment requiring maintenance.

  (2) Operation manuals and maintenance manuals for each piece of equipment requiring maintenance. Required routine maintenance actions shall be clearly identified.

  (3) Names and addresses of not less than one qualified service agency.

• CMC § 509.1 Medium relevance — show source text

  Hoods . . . . . . . . . . . . . . . . . . . . . . 114

  509.1 Grease Removal Devices. . . . . . . 114

  509.2 Installation . . . . . . . . . . . . . . . . . . 114

  509.3 Solid-Fuel Grease Removal

  Devices. . . . . . . . . . . . . . . . . . . . . 115

  510.0 Exhaust Duct Systems . . . . . . . . . 115

  510.1 General. . . . . . . . . . . . . . . . . . . . . 115

  510.2 Clearance . . . . . . . . . . . . . . . . . . . 115

  510.3 Openings . . . . . . . . . . . . . . . . . . . 115

  510.4 Listed Grease Ducts . . . . . . . . . . . 116

  510.5 Other Grease Ducts . . . . . . . . . . . 116

  510.6 Exterior Installations . . . . . . . . . . . 117

  xxxii

  510.7 Interior Installations . . . . . . . . . . . 118

  510.8 Underground Installations. . . . . . . 118

  510.9 Termination of Type I Hood Exhaust System . . . . . . . . . . . . . . 119

  510.10 Solid-Fuel Duct Systems . . . . . . . 120

  511.0 Air Movement . . . . . . . . . . . . . . . . 120

  511.1 Exhaust Fans for Commercial

  Cooking Operations . . . . . . . . . . . 120

  511.2 Airflow. . . . . . . . . . . . . . . . . . . . . . 121

  511.3 Makeup Air . . . . . . . . . . . . . . . . . . 122

  511.4 Common Duct (Manifold) Systems . . . . . . . . . . . . . . . . . . . . 122

  511.5 Solid-Fuel Air Movement

  Requirements . . . . . . . . . . . . . . . . 122

  512.0 Auxiliary Equipment . . . . . . . . . . . 122

  512.1 Dampers . . . . . . . . . . . . . . . . . . . . 122

  512.2 Electrical Equipment. . . . . . . . . . . 122

  512.3 Other Equipment . . . . . . . . . . . . . 123

  512.4 Solid-Fuel Auxiliary Equipment. . . 123

  513.0 Fire-Extinguishing Equipment. . . . 123

  513.1 General. . . . . . . . . . . . . . . . . . . . . 123

  513.2 Types of Equipment . . . . . . . . . . . 123

  513.3 Simultaneous Operation . . . . . . . . 124

  513.4 Fuel and Electric Power Shutoff . . 125

  513.5 Manual Actuation . . . . . . . . . . . . . 125

  513.6 System Annunciation . . . . . . . . . . 125

  513.7 Special Design and Application . . 125

  513.8 Review and Certification. . . . . . . . 125

• CMC § 8.13.6 Medium relevance — show source text

  [ASHRAE 15:8.13.6]

  »

  (1) Operated, where occupied, to supply not less than 0.5 CFM/ft [2] [2.54 L/(s•m [2] )] of machinery room area or 20 cubic feet per minute (9.44 L/s) per person.

  (2) Operable, where occupied at a volume required to not exceed the higher of a temperature rise of 18°F (10°C) above inlet air temperature or a maximum temperature of 122°F (50°C).

  1106.4 Natural Ventilation. When a refrigerating system is located outdoors more than 20 feet (6096 mm) from building openings and is enclosed by a penthouse, lean-to, or other open structure, natural or mechanical ventilation shall be provided. The requirements for such natural ventilation shall be in accordance with the following:

  (1) The free-aperture cross section for the ventilation of a machinery room shall be not less than as determined in accordance with Equation 1106.4.

  F = √ G (Equation 1106.4)

  Where:

  F = The free opening area, ft [2] (m [2] ).

  G = The mass of refrigerant in the largest system, any part of which is located in the machinery room, pounds.

  For SI units: 1 square foot = 0.0929 m [2], 1 pound = 0.453 kg

  (2) Locations of the gravity ventilation openings shall be based on the relative density of the refrigerant to air.

  [ASHRAE 15:8.14]

  1106.5 Combustion Air. No open flames that use combustion air from the machinery room shall be installed where refrigerant is used. Combustion equipment shall not be installed in the same machinery room with refrigerant-containing equipment except under one of the following conditions:

  (1) Combustion air shall be ducted from outside the machinery room and sealed in such a manner as to prevent refrigerant leakage from entering the combustion chamber.

  (2) A refrigerant detector, that is in accordance with Section 1106.2.5, shall be installed to automatically shut down the combustion process in the event of refrigerant leak age.

  Exception: Machinery rooms where carbon dioxide (R-744) or water (R-718) is the refrigerant.

  1106.6 Ventilation Intake. Makeup air intakes to replace the exhaust air shall be provided to the refrigeration machinery room directly from outside the building. Intakes shall be located as required by other sections of the code and fitted with backdraft dampers or other approved flow-control means to prevent reverse flow. Distribution of makeup air shall be arranged to provide thorough mixing within the refrigeration machinery room to prevent short circuiting of the makeup air directly to the exhaust.

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  REFRIGERATION

  1106.11.6.1 Mechanical Ventilation. The machinery room shall have a mechanical ventilation system in accordance with Section 1106.11.11. The mechanical ventilation system shall:

  (1) Run continuously, and failure of the mechanical ventilation system actuates an alarm, or

• CMC § 511.3 Medium relevance — show source text

  E NET = E HOOD – MA ID (Equation 511.3)

  Where:

  E NET = net hood exhaust, CFM (L/s)

  E HOOD = total hood exhaust, CFM (L/s)

  MA ID = makeup air, internal discharge, CFM (L/s)

  For SI units: 1 cubic foot per minute = 0.0283 m [3] /min, 1 cubic foot per

  minute = 0.4719 L/s

  511.3.1 Air Balance. Design plans for a facility with a commercial kitchen ventilation system shall include a schedule or diagram indicating the design outdoor air balance. The design outdoor air balance shall indicate the exhaust and replacement air for the facility and the net exfiltration where applicable. The total replacement airflow rate shall equal the total exhaust airflow rate and the net exfiltration.

  511.4 Common Duct (Manifold) Systems. Master kitchen exhaust ducts that serve multiple tenants shall include provision to bleed air from outdoors or from adjacent spaces into the master exhaust duct where required to maintain the necessary minimum air velocity in the master exhaust duct.

  [NFPA 96:8.4.1]

  511.4.1 Connections. Bleed air ducts shall connect to the top or side of the master exhaust duct. [NFPA 96:8.4.2] 511.4.2 Fire Damper. The bleed-air duct shall have a fire damper at least 12 inches (305 mm) from the exhaust duct connection. [NFPA 96:8.4.3]

  511.4.3 Construction and Clearance. The bleed-air

  duct shall have the same construction and clearance requirements as the main exhaust duct from the connection to the exhaust duct to at least 12 inches (305 mm) on both sides of the fire damper. [NFPA 96:8.4.4] 511.4.4 Adjustment. Each bleed air duct shall have a means of adjusting (e.g., by using volume dampers) the bleed air quantity. [NFPA 96:8.4.5] 511.4.5 Adjustment Location. Means to adjust the bleed air quantity shall be installed between the fire damper and the source of bleed air. [NFPA 96:8.4.6]

  511.4.6 Bleed Air Duct. A bleed air duct shall not be used for the exhaust of grease-laden vapors and shall be so labeled. [NFPA 96:8.4.7]

  511.4.7 Disconnect. Unused tenant exhaust connec tions to the master exhaust duct that are not used as bleed

  air connections shall be disconnected and sealed at the main duct. [NFPA 96:8.4.8] 511.5 Solid-Fuel Air Movement Requirements. Where solid-fuel cooking equipment is used, exhaust and replacement air also shall be in accordance with Section 517.0.

  512.0 Auxiliary Equipment.

  512.1 Dampers. Dampers shall not be installed in exhaust ducts or exhaust duct systems. [NFPA 96:9.1.1]

• CMC § 805.12.1.2 Medium relevance — show source text

  hardware is installed on equipment by the manufacturer, and that equipment make and model include factory-installed FDD hardware that match the information indicated on copies of the manufacturer’s cut sheets and on the plans and specifications.

  This procedure applies to fault detection and diagnostics (FDD) system for direct-expansion packaged units containing the following features:

  (1) The unit shall include a factory-installed economizer and shall limit the economizer dead band to not more than 2°F (-17°C).

  (2) The unit shall include direct-drive actuators on outside air and return air dampers.

  (3) The unit shall include an integrated economizer with either differential dry-bulb or differential enthalpy control.

  (4) The unit shall include a low temperature lockout on the compressor to prevent coil freeze-up or comfort problems.

  (5) Outside air and return air dampers shall have maximum leakage rates in accordance to this appendix.

  (6) The unit shall have an adjustable expansion control device such as a thermostatic expansion valve (TXV).

  (7) To improve the ability to troubleshoot charge and compressor operation, a high-pressure refrigerant port will be located on the liquid line. A low-pressure refrigerant port will be located on the suction line.

  (8) The following sensors shall be permanently installed to monitor system operation, and the controller shall have the capability of displaying the value of each parameter:

  (a) Refrigerant suction pressure

  (b) Refrigerant suction temperature

  (c) Liquid line pressure

  (d) Liquid line temperature

  (e) Outside air temperature

  (f) Outside air relative humidity

  (g) Return air temperature

  (h) Return air relative humidity

  (i) Supply air temperature

  (j) Supply air relative humidity

  The controller will provide system status by indicating the following conditions:

  (1) Compressor enabled

  (2) Economizer enabled

  (3) Free cooling available

  (4) Mixed air low limit cycle active

  (5) Heating enabled

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  APPENDIX E

  The unit controller shall have the capability to manually initiate each operating mode so that the operation of compressors, economizers, fans, and heating system can be independently tested and verified.

  E 805.12.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

  Step 1: Test low airflow condition by replacing the existing filter with a dirty filter or appropriate obstruction.

  Step 2: Verify that the fault detection and diagnostics system reports the fault.

  Step 3: Verify that the system is able to verify the correct refrigerant charge.

  Step 4: Calibrate outside air, return air, and supply air temperature sensors. E 805.12.2 Acceptance Criteria. The system is able to detect a low airflow condition and report the fault. The system is able to detect where refrigerant charge is low or high and the fault is reported. E 805.13 Automatic Fault Detection Diagnostics (FDD) for Air Handling Units (AHU) and Zone Termi- nal Units (Form MECH-13A). The purpose of this test is to verify that the system detects common faults in air handling units and terminal units. FDD systems for air handling units and zone terminal units require DDC controls to the zone level. Successful completion of this test provides a compliance credit where using the performance approach.

• CMC § 910.5 Medium relevance — show source text

  910.5 Maintenance and testing. Maintenance and testing of smoke and heat vents and mechanical smoke removal systems shall be in accordance with Sections 910.5.1 and 910.5.2. A written record of inspection, testing and maintenance that includes the date, identification of personnel involved, any unsatisfactory result, corrective action taken and replaced parts shall be maintained on the premises.

  910.5.1 Smoke and heat vents. Smoke and heat vents shall be maintained in an operative condition. Inspection, testing and maintenance shall be in accordance with NFPA 204 except as follows:

  1. Mechanically operated smoke and heat vents shall be inspected annually and operationally tested not less than every 5

  years. 2. Gravity dropout smoke and heat vents shall be inspected annually. 3. Fused, damaged or painted fusible links shall be replaced.

  910.5.2 Mechanical smoke removal systems. Mechanical smoke removal systems shall be maintained in accordance with NFPA 204 and the equipment manufacturer’s instructions except as follows:

  1. Systems shall be inspected and operationally tested annually.
  2. Testing shall include the operation of all system components, controls and ancillary equipment, such as makeup air openings.
  3. A written schedule for routine maintenance and operational testing shall be established and testing shall be conducted in accordance with the schedule.

  SECTION 911—EXPLOSION CONTROL

  911.1 General. Explosion control shall be provided in the following locations:

  1. Where a structure, room or space is occupied for purposes involving explosion hazards as identified in Table 911.1.
  2. Where quantities of hazardous materials specified in Table 911.1 exceed the maximum allowable quantities in Table 5003.1.1(1).

  Such areas shall be provided with explosion (deflagration) venting, explosion (deflagration) prevention systems or barricades in accordance with this section and NFPA 68, NFPA 69 or NFPA 495 as applicable. Deflagration venting shall not be utilized as a means to protect buildings from detonation hazards.

  TABLE 911.1—EXPLOSION CONTROL REQUIREMENTSf	Col2	Col3	Col4
  MATERIAL	CLASS	EXPLOSION CONTROL METHODS	EXPLOSION CONTROL METHODS
  MATERIAL	CLASS	Barricade construction	Explosion (deflagration) venting or explosion (deflagration) prevention systems
  Hazard Category	Hazard Category	Hazard Category	Hazard Category
  Combustible dustsa	—	Not required	Required
  Cryogenic fluids	Flammable	Not required	Required

  2025 CALIFORNIA FIRE CODE 9-67

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  FIRE PROTECTION AND LIFE SAFETY SYSTEMS

  |TABLE 911.

• CMC § 516.0 Medium relevance — show source text

  516.0 Recirculating Systems. 516.1 General Requirements. Recirculating systems containing or for use with appliances used in processes producing smoke or grease-laden vapors shall be equipped with components complying with the following:

  (1) The clearance requirements of Section 507.4 through Section 507.4.3.3.

  (2) A hood complying with the requirements of Section 508.0.

  (3) Grease removal devices complying with Section 509.0.

  (4) The air movement requirements of Section 511.2.1 and Section 511.2.2.

  (5) Auxiliary equipment (such as particulate and odor removal devices) complying with Section 512.0.

  (6) Fire-extinguishing equipment complying with the requirements of Section 513.0.

  Exception: Fire-extinguishing equipment in accordance with Section 513.1 and Section 513.5.

  (7) The use and maintenance requirements of Section 514.0.

  (8) The minimum safety requirements of Section 515.0.

  (9) All the requirements of Section 516.0. [NFPA 96:14.1]

  516.2 Design Restrictions. All recirculating systems shall comply with the requirements of Section 516.2.1 through Section 516.2.9. [NFPA 96:14.2]

  516.2.1 Gas/Electrically Fueled Cooking Appli- ances. Only gas-fueled or electrically fueled cooking appliances shall be used. Listed gas-fueled equipment designed for use with specific recirculating systems shall have the flue outlets connected in the intended manner. Gas-fueled appliances shall have a minimum 18 inches (457 mm) clearance from the flue outlet to the filter inlet in accordance with Section 509.2.2 through Section 509.2.2.3 and shall meet the installation requirements of this code, NFPA 54/ANSI Z223.1 or NFPA 58. {NFPA 96:14.2.1 – 14.2.3}

  516.2.2 Recirculation. Recirculating systems shall be listed with a testing laboratory in accordance with UL 710B or equivalent. [NFPA 96:14.2.4]

  516.2.3 Protection. Cooking appliances that require protection and that are under a recirculating hood shall be protected by either the integral fire protection system in accordance with UL 710B or a system in accordance with Section 513.0. [NFPA 96:14.2.4.2]

  516.2.4 Maximum Limits. A recirculating system shall not use cooking equipment that exceeds that recirculating system’s labeled maximum limits for that type of equipment, stated in maximum energy input, maximum cooking temperature, and maximum square area of cooking surface or cubic volume of cooking cavity. [NFPA 96:14.2.6]

  516.2.5 Label. The listing label shall show the type(s) of cooking equipment tested and the maximum limits specified in Section 516.2.4. [NFPA 96:14.2.7]

  516.2.6 Fire Damper. A fire-actuated damper shall be installed at the exhaust outlet of the system. [NFPA 96:14.2.8] The actuation device for the fire damper shall have a maximum temperature rating of 375°F (191°C).

  [NFPA 96:14.2.10]

• CMC § 8.1.3.2 Medium relevance — show source text

  CONNECTION–SEALANT METHOD

  [NFPA 96: FIGURE 8.1.3.2(c)]

  FIGURE 511.1.2(4) TYPICAL SECTION OF DUCT-TO-FAN CONNECTION-DIRECT

  TO FAN INLET CONE METHOD

  [NFPA 96: FIGURE 8.1.3.2(d)]

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  EXHAUST SYSTEMS

  511.2.2.1 Performance Test. A performance test shall be conducted upon completion and before final approval of the installation of a ventilation system serving commercial cooking appliances. The test shall verify the rate of exhaust airflow in accordance with Section 508.5.1.2 through Section 508.5.1.5. The permit holder shall furnish the necessary test equipment and devices required to perform the tests.

  [ASHRAE 154:4.7.1]

  511.2.2.2 Capture and Containment Test. The permit holder shall verify the capture and containment performance of Type I hoods. A field test shall be conducted with all appliances under the hood at operating temperatures, all the hoods operating at design airflows, and with all sources of replacement air operating at design airflows for the restaurant. Capture and containment shall be verified visually by observing smoke or steam produced by actual cooking operation or by simulating cooking using devices such as smoke candles or smoke puffers. Smoke bombs shall not be used. [ASHRAE 154:4.7.2]

  511.2.3 Exhaust Fan Operation. A hood exhaust fan(s) shall continue to operate after the extinguishing system has been activated unless fan shutdown is required by a listed component of the ventilation system or by the design of the extinguishing system. The hood exhaust fan shall start upon actuation of the extinguishing system if the exhaust fan and all cooking equipment served by the fan have been shut down, unless fan shutdown is required by a listed component of the ventilation system or by the listing of the extinguishing system. The exhaust fan shall be provided with a means so that the fan is activated when any heat-producing cooking appliance under the hood is turned on. [NFPA 96:8.2.3.1 – 8.2.3.3]

  511.3 Makeup Air. The makeup air quantity shall prevent negative pressures in the commercial cooking area(s) from exceeding 0.02 inch water column (0.005 kPa). Where the fire-extinguishing system activates, makeup air supplied internally to a hood shall be shut off.

  For compensating hoods, where a Type I or Type II hood has an internal discharge of makeup air, the makeup air flow shall not exceed 10 percent of the exhaust airflow, the exhaust airflow shall be the net exhaust from the hood in accordance with Section 508.5.1.2 through Section 508.5.1.5. The total hood exhaust shall be determined in accordance with Equation 511.3.

  E NET = E HOOD – MA ID (Equation 511.3)

  Where:

  E NET = net hood exhaust, CFM (L/s)

  E HOOD = total hood exhaust, CFM (L/s)

• CMC § 1106.2.9. Medium relevance — show source text

  1106.2.9.

  1106.2.8 Ventilation. Mechanical ventilation referred

  to in Section 1106.2.7 shall be by one or more powerdriven fans capable of exhausting air from the machinery room at not less than the amount shown in accordance

  with Section 1106.2.9.

  To obtain a reduced airflow for normal ventilation, multiple fans or multispeed fans shall be used. Provision shall be made to supply makeup air to replace that being exhausted. Ducts for supply and exhaust to the machinery room shall serve no other area. The makeup air supply locations shall be positioned relative to the exhaust air locations to avoid short-circuiting. Inlets to the exhaust ducts shall be located in an area where refrigerant from a leak will concentrate, in consideration of the location of the replacement supply air paths, refrigerating machines, and the density of the refrigerant relative to air.

  Inlets to exhaust ducts shall be within 1 foot (305 mm) of the lowest point of the machinery room for refrigerants that are heavier than air, and shall be within 1 foot (305 mm) of the highest point for refrigerants that are lighter than air. The discharge of the exhaust air shall be to the outdoors in such a manner as not to cause a nuisance or danger.

  1106.2.9 Emergency Ventilation-Required Air- flow. An emergency ventilation system shall be required to exhaust an accumulation of refrigerant due to leaks or a rupture of the system. The emergency ventilation required shall be capable of removing air from the machinery room in not less than the airflow quantity in Section 1106.2.9.1. Where multiple refrigerants are present, then the highest airflow quantity shall apply.

  1106.2.9.1 Ventilation - A1, A2, A3, B1, B2 and B3 Refrigerants. The emergency ventilation for A1, A2, A3, B1, B2 and B3 refrigerants shall have the capacity to provide mechanical exhaust at a rate as determined in accordance with Equation 1106.2.9.1.

  Q = 100 √ G (Equation 1106.2.9.1)

  Where:

  Q = Air flow rate, CFM.

  G = Refrigerant mass in largest system, pounds.

  For SI units: 1 pound = 0.453 kg, 1 cubic foot per minute =

  0.0283 m [3] /min, 1 cubic foot per minute = 0.4719 L/s

  1106.3 Normal Operation. A part of the refrigeration machinery room mechanical ventilation shall be in accordance with the following:

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