Chapter 3 — GENERAL REGULATIONS

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 3

GENERAL REGULATIONS

This chapter covers general requirements for heating, ventilating, air-conditioning, refrigeration, miscellaneous heat-producing, and energy-utilizing equipment or appliances. Such equipment or appliances shall comply with the requirements of this code.

by the Authority Having Jurisdiction for safe use or comply with applicable nationally recognized standards as evidenced by the listing and label of an approved agency. A list of accepted standards is included in Chapter 18. Defective materials or parts shall be replaced in such a manner as not to invalidate an approval.

shall furnish satisfactory evidence that the appliance is constructed in accordance with the requirements of this code. The permanently attached label of an approved agency shall be permitted to be accepted as such evidence.

by this code:

(1) Equipment requiring electrical connections of more than 50 volts shall have a positive means of disconnect adjacent to and in sight from the equipment served.

Exception: Other power disconnect means shall be acceptable where in accordance with the California Elec- trical Code .

(2) A 120 volt receptacle shall be located within 25 feet (7620 mm) of the equipment for service and maintenance purposes. The receptacle outlet shall be on the supply side of the disconnect switch. The receptacle need not be located on the same level as the equipment.

(3) Electrical wiring, controls, and connections to equipment and appliances regulated by this code shall be in accordance with the California Electrical Code .

valves for appliances burning oil shall be installed in accordance with the requirements of NFPA 31.

A metal guard shall be provided around exposed flywheels, fans, pulleys, belts, and moving machinery that are portions of a heating, ventilating, or refrigerating system.

Section 309 of California Existing Building Code for general requirements.

appliances, appurtenances, equipment, materials, and devices used in a mechanical system shall be listed (third-party certified) by a listing agency (accredited conformity assessment

body) as complying with the approved applicable recognized standards referenced in this code, and shall be free from defects. Unless otherwise provided for in this code, materials, appurtenances, or devices used or entering into the construction of mechanical systems, or parts thereof, shall be submitted to the Authority Having Jurisdiction for approval prior to being installed.

302.1.1 Marking. Each length of pipe and each pipe fitting, material, and device used in a mechanical system shall have cast, stamped, or indelibly marked on it any markings required by the applicable referenced standards and listing agency, and the manufacturer’s mark or name, which shall readily identify the manufacturer to the end user of the product. Where required by the approved standard that applies, the product shall be marked with the weight and the quality of the product. Materials and devices used or entering into the construction of mechanical systems, or parts thereof, shall be marked and identified in a manner satisfactory to the Authority Having Jurisdiction. Such marking shall be done by the manufacturer. Field markings shall not be acceptable.

Exception: Markings shall not be required on nipples created from cutting and threading of approved pipe.

302.1.2 Standards. Standards listed or referred to in this chapter or other chapters cover materials that will conform to the requirements of this code, where used in accordance with the limitations imposed in this or other chapters thereof and their listing. Where a standard covers materials of various grades, weights, quality, or configurations, the portion of the listed standard that is applicable shall be used. Design and materials for special conditions or materials not provided for herein shall be permitted to be used by special permission of the Authority Having Jurisdiction after the Authority Having Jurisdiction has been satisfied as to their adequacy. A list of mechanical standards that appear in specific sections of this code is referenced in Table 1801.1. Standards referenced in Table 1801.1 shall be applied as indicated in the applicable referenced section. A list of additional approved standards, publications, practices and guides that are not referenced in specific sections of this code appear in Table 1801.2.

302.1.3 Existing Buildings. In existing buildings or premises in which mechanical installations are to be altered, repaired, or renovated, the Authority Having Jurisdiction has discretionary powers to permit deviation from the provisions of this code, provided that such proposal to deviate is first submitted for proper determination in order that health and safety requirements, as they pertain to mechanical systems, shall be observed.

tion Equivalency. Nothing in this code is intended to pre

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vent the use of systems, methods, or devices of equivalent or superior quality, strength, fire resistance, effectiveness, durability, and safety over those prescribed by this code. Technical documentation shall be submitted to the Authority Having Jurisdiction to demonstrate equivalency. The Authority Having Jurisdiction shall have the authority to approve or disapprove the system, method, or device for the intended purpose.

However, the exercise of this discretionary approval by the Authority Having Jurisdiction shall have no effect beyond the jurisdictional boundaries of said Authority Having Jurisdiction. An alternate material or method of construction so approved shall not be considered as in accordance with the requirements, intent, or both of this code for a purpose other than that granted by the Authority Having Jurisdiction where the submitted data does not prove equivalency.

302.2.1 Testing. The Authority Having Jurisdiction shall have authority to require tests, as proof of equivalency.

302.2.1.1 Tests. Tests shall be made in accordance with approved testing standards, by an approved testing agency at the expense of the applicant. In the absence of such standards, the Authority Having Jurisdiction shall have the authority to specify the test procedure.

302.2.1.2 Request by the Authority Having Jurisdiction. The Authority Having Jurisdiction shall have the authority to require tests to be made or repeated where there is reason to believe that a material or device no longer is in accordance with the requirements on which its approval was based.

engineered design shall comply with the intent of the provisions of this code and shall provide an equivalent level of quality, strength, effectiveness, fire resistance, durability, and safety. Material, equipment, or components shall be designed and installed in accordance with the manufacturer’s installa tion instructions.

302.3.1 Permit Application. The registered design professional shall indicate on the design documents that the mechanical system, or parts thereof, is an alternative engineered design so that it is noted on the construction permit application. The permit and permanent permit records shall indicate that an alternative engineered design was part of the approved installation.

302.3.2 Technical Data. The registered design professional shall submit sufficient technical data to substantiate the proposed alternative engineered design and to prove that the performance meets the intent of this code.

302.3.3 Design Documents. The registered design professional shall provide two complete sets of signed and sealed design documents for the alternative engineered design for submittal to the Authority Having Jurisdiction. The design documents shall include floor plans of the work. Where appropriate, the design documents shall indicate location, sizing, and loading of appurtenances, equipment, appliances, and devices.

302.3.4 Design Approval. An approval of an alternative engineered design shall be at the discretion of the Authority Having Jurisdiction. The exercise of this discretionary approval by the Authority Having Jurisdiction shall have no effect beyond the jurisdictional boundaries of said Authority Having Jurisdiction. An alternative engineered design so approved shall not be considered as in accordance with the requirements, intent, or both of this code for a purpose other than that granted by the Authority Having Jurisdiction.

302.3.5 Design Review. The Authority Having Jurisdiction shall have the authority to require testing of the alternative engineered design in accordance with Section 302.2.1, including the authority to require an independent review of the design documents by a registered design professional selected by the Authority Having Jurisdiction and at the expense of the applicant.

302.3.6 Inspection and Testing. The alternative engineered design shall be tested and inspected in accordance with the submitted testing and inspection plan and the requirements of this code.

and appliances regulated by this code shall be in accordance with the conditions of the listing, the manufacturer’s installation instructions and this code. The manufacturer’s instal lation and operating instructions shall be attached to the appliance. Clearances of listed equipment and appliances from combustible materials shall be as specified in the listing or on the rating plate.

for OSHPD 1, 1R, 2, 3, 4 & 5] Central heating furnaces and boilers installed in closets or alcoves shall be listed for such

installation. Central heating furnaces not listed for closet or alcove installation shall be installed in a room or space having a volume not less than 12 times the total volume of the furnace. Central heating boilers not listed for closet or alcove installation shall be installed in a room or space having a volume 16 times the volume of the boiler. Where the ceiling height of the room or space exceeds 8 feet (2438 mm), the volume shall be calculated on the basis of an 8 foot (2438 mm) height.

The installation clearances shall be in accordance with

the appliance listing, shall not be reduced, and shall be installed in accordance with Section 904.3.

Except as otherwise permitted in this code, unlisted equipment and appliances shall be approved by the Authority Having Jurisdiction prior to being installed. Unlisted equipment and appliances shall be installed in accordance with the manufacturer’s installation instruc tions and with clearances from combustible materials in

accordance with Section 303.10 or Section 303.10.1.

be fixed in position shall be securely fastened in place in

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GENERAL REGULATIONS

accordance with the manufacturer’s installation instructions.

Supports for appliances shall be designed and constructed to sustain vertical and horizontal loads within the stress limita tions specified in the building code.

casters shall be limited by a restraining device installed in accordance with the connector and appliance manufacturer’s installation instructions. [NFPA 54:9.6.1.4]

heating, cooling, ventilating, or refrigerating system is installed on the roof of a building or within a building, it shall be permanently identified as to the area or space served by the equipment.

Containers, container valves regulating equipment, and appurtenances for the storage and supply of liquefied petroleum gas (LP-Gas) shall be installed in accordance with NFPA 58 and the California Fire Code .

303.7.1 Liquefied Petroleum Gas (LP-Gas) Appli- ances. [HCD 1 & HCD 2] Liquefied petroleum gas- burning appliances shall not be installed in a pit, basement, or similar location where heavier-than-air gas might collect. Appliances so fueled shall not be installed in an above-grade under-floor space or basement unless such location is provided with an approved means for removal of unburned gas.

designed or enclosed so as to withstand climatic conditions in the area in which they are installed. Where enclosures are provided, each enclosure shall permit easy entry and movement, shall be of reasonable height, and shall have at least a 30 inch (762 mm) clearance between the entire service access panel(s) of the appliance and the wall of the enclosure. [NFPA 54:9.4.1.1]

303.8.1 Load Capacity. Roofs on which appliances are to be installed shall be capable of supporting the additional load or shall be reinforced to support the additional load. [NFPA 54:9.4.1.2]

303.8.2 Fasteners. All access locks, screws, and bolts shall be of corrosion-resistant material. [NFPA 54:9.4.1.3]

303.8.3 Installation of Appliances on Roofs. Appliances shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:9.4.2.1]

303.8.4 Edge of Roof Clearance. Appliances shall be installed on a well-drained surface of the roof. At least 6 feet (1829 mm) of clearance shall be available between any part of the appliance and the edge of a roof or similar hazard, or rigidly fixed rails, guards, parapets, or other building structures at least 42 inches (1067 mm) in height shall be provided on the exposed side. [NFPA 54:9.4.2.2]

303.8.4.1 Guards and Rails. Guards or rails shall be required where the following exist:

(1) The clearance between the appliance and a roof edge or open end of an equipment platform is less than 6 feet (1829 mm).

(2) The open end of the equipment platform is located more than 30 inches (762 mm) above the roof, floor, or grade below.

Where guards or rails are installed, they shall be constructed so as to prevent the passage of a 21 inch (533 mm) diameter ball, resist the imposed loading conditions, and shall extend not less than 30 inches (762 mm) beyond each side of the equipment or appliance.

Exception: Guards shall not be required where a permanent fall arrest anchorage connector system in accordance with ASSP Z359.1 is installed.

303.8.5 Electrical Power. Appliances requiring an external source of electrical power shall be installed in accordance with the California Electrical Code . [NFPA 54:9.4.2.3]

303.8.6 Platform or Walkway. Where water stands on the roof at the appliance or in the passageways to the appliance, or where the roof is of a design having a water seal, a suitable platform, walkway, or both shall be provided above the water line. Such platform(s) or walkway(s) shall be located adjacent to the appliance and control panels so that the appliance can be safely serviced where water stands on the roof. [NFPA 54:9.4.2.4]

be supported and connected to the piping so as not to exert undue strain on the connections. [NFPA 54:9.1.16]

Appliances and their vent connectors shall be installed with clearances from combustible material so their operation does not create a hazard to persons or property. Minimum clearances between combustible walls and the back and sides of various conventional types of appliances and their vent connectors are specified in Chapter 8 and Chapter 9, or NFPA 211.

[NFPA 54:9.2.2] Where not provided in this code, listed and unlisted equipment or appliances shall be installed to maintain the required clearances for servicing and to combustible construction in accordance with the listing and the manufacturer’s installation instructions.

303.10.1 Clearance Reduction. Reduced clearances to combustible construction for listed equipment and appliances shall comply with the listing and Table 303.10.1. Where permitted by the manufacturer, and not provided in this code, reduced clearances to combustible construction for unlisted equipment and appliances shall comply with Table 303.10.1. 303.10.1.1 Type I Hood Exhaust System. Reduced clearances for Type I exhaust systems shall be in accordance with Section 507.4.2 through Section 507.4.2.3. Clearances from the duct or the

exhaust fan to the interior surface of enclosures of

combustible construction shall be in accordance with

Section 510.7.3 and clearances shall not be reduced.

303.10.1.2 Product Conveying Ducts. Reduced clearances to combustibles construction for product conveying ducts shall be in accordance with Section 506.10.3 through Section 506.11.6.3.

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GENERAL REGULATIONS

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303.10.1.3 Solid-Fuel-Burning Appliances. For solid-fuel-burning appliances, the clearance shall not be less than 12 inches (305 mm) to combustible walls and not less than 18 inches (457 mm) to combustible ceilings. The clearance, after reduction, shall be permitted to be less than 12 inches (305 mm) to combustible walls and less than 18 inches (457 mm) to combustible ceilings. Solid-fuel-burning appliances listed for lesser clearances shall be permitted to be installed in accordance with the manufacturer’s instructions and their listing.

Appliances installed in commercial garages shall be in accordance with Section 303.11.1 through Section 303.11.2. 303.11.1 Parking Structures. Appliances installed in enclosed, basement, and underground parking structures shall be installed in accordance with NFPA 88A. [NFPA 54:9.1.11.1] 303.11.2 Repair Garages. Appliances installed in repair garages shall be installed in accordance with NFPA 30A. [NFPA 54:9.1.11.2]

Heaters in aircraft hangars shall be installed in accordance with NFPA 409.

[NFPA 54:9.1.12]

to building construction and other equipment so as to permit access for repair or replacement of the appliance. Clearance shall be maintained to permit removal of the appliance; cleaning of heating surfaces; the replacement of filters, blowers, motors, burners, controls, and vent connections; the lubrication of moving parts where necessary; the adjustment and cleaning of burners and pilots; and the proper functioning of explosion vents, if provided. For attic installation, the passageway and servicing area adjacent to the appliance shall be in accordance with Section 304.4. {NFPA 54:9.2.1}

Unless otherwise specified, clearances of not less than 30 inches (762 mm) in depth, width, and height of working space shall be maintained.

Exception: A platform shall not be required for unit heaters or room heaters.

require service are installed on a roof having a slope of 4 units vertical in 12 units horizontal (33 percent slope) or more, a level platform of not less than 30 inches by 30 inches (762 mm by 762 mm) shall be provided at the service side of the equipment or appliance.

located on roofs or other elevated locations shall be accessible. [NFPA 54:9.4.3.1]

304.3.1 Access from the Inside. Buildings of more than 15 feet (4572 mm) in height shall have an inside means of access to the roof unless other means acceptable to the Authority Having Jurisdiction are used. [NFPA 54:9.4.3.2]

304.3.1.1 Access Type. The inside means of access shall be a permanent or foldaway inside stairway or ladder, terminating in an enclosure, scuttle, or trapdoor. Such scuttles or trapdoors shall be at least 22 inches by 24 inches (559 mm by 610 mm) in size, shall open easily and safely under all conditions, especially snow, and shall be constructed so as to permit access from the roof side unless deliberately locked on the inside.

At least 6 feet (1829 mm) of clearance shall be available between the access opening and the edge of the roof or similar hazard, or rigidly fixed rails or guards a minimum of 42 inches (1067 mm) in height shall be provided on the exposed side. Where parapets or other building structures are utilized in lieu of guards or rails, they shall be a minimum of 42 inches (1067 mm) in height. [NFPA 54:9.4.3.3]

304.3.1.2 Permanent Ladders. Permanent lad ders required by Section 304.3.1.1 shall be constructed in accordance with the following:

(1) Side railings shall extend not less than 30 inches (762 mm) above the roof or parapet wall.

(2) Landings shall not exceed 18 feet (5486 mm) apart measured from the finished grade.

(3) Width shall be not less than 14 inches (356 mm)

on center.

(4) Rungs spacing shall not exceed 12 inches (305 mm) on center, and each rung shall be capable of supporting a 300 pound (136.1 kg) load.

(5) Toe space shall be not less than 6 inches (152 mm).

304.3.2 Permanent Lighting. Permanent lighting shall be provided at the roof access. The switch for such lighting shall be located inside the building near the access means leading to the roof. [NFPA 54:9.4.3.4]

An attic or under-floor space in which an appliance is installed shall be accessible through an opening and passageway larger than the largest component of the appliance, and not less than 22 inches by 30 inches (559 mm by 762 mm). {NFPA 54:9.5.1}

304.4.1 Length of Passageway. Where the height of the passageway is less than 6 feet (1829 mm), the distance from the passageway access to the appliance shall not exceed 20 feet (6096 mm) measured along the centerline of the passageway. [NFPA 54:9.5.1.1] Where the height of the passageway is 6 feet (1829 mm) or more, the distance from the passageway access to the appliance shall not exceed 50 feet (15 240 mm) measured along the centerline of the passageway.

304.4.2 Width of Passageway. The passageway shall be unobstructed and shall have solid flooring not less than 24 inches (610 mm) wide from the entrance opening to the appliance. [NFPA 54:9.5.1.2]

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GENERAL REGULATIONS

304.4.3 Work Platform. A level working platform not less than 30 inches by 30 inches (762 mm by 762 mm) shall be provided in front of the service side of the appliance. [NFPA 54:9.5.2]

Exception: A working platform need not be provided where the furnace is capable of being serviced from the required access opening. The furnace service side shall not exceed 12 inches (305 mm) from the access opening. 304.4.4 Lighting and Convenience Outlet. A permanent 120 V receptacle outlet and a luminaire shall be installed near the appliance. The switch controlling the luminaire shall be located at the entrance to the passageway. [NFPA 54:9.5.3]

in residential garages and in adjacent spaces that open to the garage and are not part of the living space of a dwelling unit shall be installed so that all heating elements, switches, burners, and burner-ignition devices are located not less than 18 inches (457 mm) above the floor. Exception: Listed flammable vapor ignition resistant (FVIR) appliances. {NFPA 54:9.1.10.1} 305.1.1 Physical Damage. Appliances installed in garages, warehouses, or other areas subject to mechanical damage shall be guarded against such damage by being installed behind protective barriers or by being elevated or located out of the normal path of vehicles. 305.1.2 Access from the Outside. Where appliances are installed in a separate, enclosed space having access only from outside of the garage, such appliances shall be permitted to be installed at floor level, providing the required combustion air is taken from the exterior of the garage. [NFPA 54:9.1.10.3] 305.1.3 Cellulose Nitrate Plastic Storage. Heating equipment located in rooms where cellulose nitrate plastic is stored or processed shall be in accordance with the fire code.

an appliance, the depth shall extend not less than 6 inches (152 mm) below and 12 inches (305 mm) on all sides of the appliance, except on the service side, which shall have 30 inches (762 mm). Where the depth of the excavation for either the appliance or passageway exceeds 12 inches (305 mm), walls shall be lined with concrete or masonry 4 inches (102 mm) above the adjoining ground level. Exception: [HCD 1 & HCD 2] Liquefied petroleum gas (LP-Gas) appliances as described in Section 303.7.1.

hazard areas, heating, ventilating, air-conditioning, refrigeration, miscellaneous heat-producing, and energy-utilizing equipment and appliances shall be elevated at or above the elevation in accordance with the building code for utilities and attendant equipment or the elevation of the lowest floor, whichever is higher. Exception: Equipment and appliances shall be permitted to be located below the elevation in accordance with the build

ing code for utilities and attendant equipment or the elevation of the lowest floor, whichever is higher, provided that the systems are designed and installed to prevent water from entering or accumulating within their components and the systems are constructed to resist hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding to such elevation.

305.3.1 Coastal High Hazard Areas. Mechanical systems in buildings located in coastal high hazard areas shall be in accordance with the requirements of Section 305.3, and mechanical systems, pipes, and appurtenances shall not be mounted on or penetrate through walls that are intended to breakaway under flood loads in accordance with the building code.

305.3.2 Air Exhaust and Intake Openings. Outside air exhaust openings and air intake openings shall be located at or above the elevation required by the building code for utilities and attendant equipment or the elevation of the lowest floor, whichever is higher.

and safety of the elevator system, mechanical systems shall not be located in an elevator shaft.

attic, in or on an attic ceiling assembly, floor-ceiling assembly, floor-subfloor assembly or where damage results from a leaking water heater, a watertight pan of corrosion-resistant materials shall be installed beneath the water heater in accordance with the following: (1) The drainage pan shall be provided with not less than [3] ⁄ 4 of an inch (20 mm) diameter drain to an approved location. The terminating end of the drainpipe shall be readily visible. (2) The drainage pan shall be not less than 1 [1] ⁄ 2 inches (38 mm) in depth.

(3) Where a drainage pan pipe is installed, the material of the piping shall be rated for the temperature rating of the water heater and shall be approved for use with the liquid being discharged.

(4) Discharge from a relief valve into a drainage pan shall be prohibited.

locations shall be in accordance with the following:

(1) Listed for outdoor installation.

(2) Provided with approved protection from the outdoor elements that can affect the operation, durability, or safety of such appliances and in accordance with the manufacturer’s installation instructions.

(3) Outdoor cooking appliances shall comply with Section 922.0.

a listed device or devices that will shut off the fuel supply to the main burner or burners in the event of pilot or ignition failure. Liquefied petroleum gas-air-burning heating appli

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ances shall be equipped with a listed automatic device or devices that will shut off the flow of gas to the pilot in the event of ignition failure.

Exception: The listed shutoff devices shall not be required on range or cooking tops, log lighters, lights, or other openburner manually operated appliances, or listed appliances not requiring such devices and specific industrial appliances as approved by the Authority Having Jurisdiction.

Heating appliances whose manual fuel controls are not readily accessible from the main portion of the building being heated shall be equipped with remote controls.

Forced-air and gravity-type warm air furnaces shall be equipped with a listed air outlet temperature limit control that cannot be set for temperatures exceeding 250°F (121°C). Such controls shall be located in the bonnet or plenum, within 2 feet (610 mm) of the discharge side of the heating element of gravity furnaces or in accordance with the conditions of listing.

Electric duct heaters shall be equipped with an approved automatic reset air outlet temperature limit control that will limit the outlet air temperature to not exceed 200°F (93°C). The electric elements of the heater shall be equipped with fusible links or a manual reset temperature limit control that will prevent outlet air temperature in excess of 250°F (121°C).

Building automation systems shall provide for localized con- trol in the event of network failure. This capability shall be specified in the construction documentation.

appliances shall bear a permanent and legible factory-applied nameplate on which shall appear:

(1) The name or trademark of the manufacturer.

(2) The approved fuel input rating of the appliance, expressed in Btu/h (kW).

(3) The model number or equivalent.

(4) The serial number.

(5) Instructions for the lighting, operation, and shutdown of the appliance.

(6) The type of fuel approved for use with the appliance.

(7) The symbol of an approved agency certifying compliance of the equipment with recognized standards.

(8) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

appliances shall bear a permanent and legible factory-applied nameplate on which shall appear:

(1) The name or trademark of the manufacturer.

(2) The model number or equivalent.

(3) The serial number.

(4) The electrical rating in volts, amperes (or watts), and, for other than single phase, the number of phases.

(5) The output rating in Btu/h (kW).

(6) The electrical rating in volts, amperes, or watts of each field-replaceable electrical component.

(7) The symbol of an approved agency certifying compliance of equipment with recognized standards.

(8) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

An appliance shall be accompanied by clear and complete installation instructions, including required clearances from combustibles other than mounting or adjacent surfaces, and temperature rating of field-installed wiring connections exceeding 140°F (60°C).

Heat pumps and electric cooling appliances shall bear a permanent and legible factory-applied nameplate on which shall

appear:

(1) The name or trademark of the manufacturer.

(2) The model number or equivalent.

(3) The serial number.

(4) The amount of refrigerant.

(5) The refrigerant designation.

(6) The factory test pressures or pressures applied.

(7) The electrical rating in volts, amperes, and, for other than single phase, the number of phases.

(8) The output rating in Btu/h (kW).

(9) The electrical rating in volts, amperes, or watts of each field replaceable electrical component.

(10)The symbol of an approved agency certifying compliance of the equipment with recognized standards.

(11)Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

An appliance shall be accompanied by clear and complete installation instructions, including required clearances from combustible other than mounting or adjacent surfaces, and temperature rating of field-installed wiring connections exceeding 140°F (60°C).

Absorption units shall bear a permanent and legible factory-applied nameplate on which shall

appear:

(1) The name or trademark of the manufacturer.

(2) The model number or equivalent.

(3) The serial number.

(4) The amount of refrigerant.

(5) The refrigerant designation.

(6) Hourly rating in Btu/h (kW).

(7) The type of fuel approved for use with the unit.

(8) Cooling capacity Btu/h (kW).

(9) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

(10)The symbol of an approved agency certifying compliance of the equipment with recognized standards.

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to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.

workmanship shall comply with accepted engineering practices and shall be of such character as to secure the results sought to be obtained by this code.

conceal cracks, holes, or other imperfections in materials by welding, brazing, or soldering, by using therein or thereon paint, wax, tar, solvent cement, other leak-sealing or repair agent.

be installed in a manner that is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All mechanical systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction.

Condensate from air washers, air-cooling coils, condensing appliances, and the overflow from evaporative coolers and similar water-supplied equipment or similar air-conditioning equipment shall be collected and discharged to an approved plumbing fixture or disposal area. Where discharged into the drainage system, equipment shall drain by means of an indirect waste pipe. The waste pipe shall have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope and shall be of approved corrosion-resistant material not smaller than the outlet size in

accordance with Section 310.3 or Section 310.4 for air-cooling coils or condensing appliances, respectively. Condensate or wastewater shall not drain over a public way.

310.1.1 Condensate Pumps. Where approved by the Authority Having Jurisdiction, condensate pumps shall be installed in accordance with the manufacturer’s installation instructions. Pump discharge shall rise vertically to a point where it is possible to connect to a gravity condensate drain and discharged to an approved disposal point. Each condensing unit shall be provided with a separate sump and interlocked with the equipment to prevent the equipment from operating during a failure. Separate pumps shall be permitted to connect to a single gravity indirect waste where equipped with check valves and approved by the Authority Having Jurisdiction.

appliance is installed in a space where damage is capable of resulting from condensate overflow, a drain line shall be provided and shall be drained in accordance with Section 310.1. An additional protection method for condensate overflow shall be provided in accordance with one of the following:

(1) A water level detecting device that will shut off the equipment or appliance in the event the primary drain is

For SI units: 1 ton of refrigeration = 3.52 kW, 1 inch = 25 mm

The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running threequarters full at the following pipe conditions:

For SI units: °C = (°F-32)/1.8

blocked. Such detecting device shall be in accordance with the manufacturer’s installation instructions.

(2) An additional watertight pan of corrosion-resistant material, with a separate drain line, installed beneath the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain.

(3) An additional separate drain line at a level that is higher than the primary drain line connection of the drain pan.

(4) An additional watertight pan of corrosion-resistant material with a water level detection device installed beneath

the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain and to shut off the equipment.

The additional pan or the additional drain line connection shall be provided with a drain pipe of not less than [3] ⁄ 4 of an inch (20 mm) nominal pipe size, discharging at a point that is readily observed.

310.2.1 Protection of Appurtenances. Where insulation or appurtenances are installed where damage is capable of resulting from a condensate drain pan overfill, such installations shall occur above the rim of the drain

pan with supports. Where the supports are in contact with the condensate waste, the supports shall be of approved corrosion-resistant material.

Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 310.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment, and shall be approved for use with the liquid being discharged.

TABLE 310.3

MINIMUM CONDENSATE PIPE SIZE

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Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.

Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in the plumbing code. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.

310.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut.

lines from individual condensing appliances shall be sized as required by the manufacturer’s instructions. Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer.

waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 310.4.

Coils. Where the condensate waste from air-conditioning coils discharges by direct connection to a lavatory tailpiece or to an approved accessible inlet on a bathtub overflow, the connection shall be located in the area controlled by the same person controlling the air-conditioned space.

screwed fittings shall be used with plastic male fittings and plastic male threads. Female plastic threaded connections shall not be allowed to be used when threaded onto a male

metallic connection.

A heating or cooling air system shall be provided with return air, outside air, or both. A heating or cooling air system regulated by this code and designed to replace required ventilation shall be arranged to discharge into a conditioned space not less than the amount of outside air specified in Chapter 4.

cooling, or makeup air system. Media-type air filters shall comply with UL 900. Electrostatic and high efficiency particulate filters shall comply with Section 935.0.

Exceptions:

(1) Air filters used in systems serving single guest rooms or dwelling units shall not be required to be listed.

(2) Air filters used in listed appliances and in accordance with the manufacturer’s instructions.

311.2.1 Minimum Filtration. In mechanically ventilated buildings, occupied areas of the building shall be provided with air filtration media for outside and return air that provides not less than a Minimum Efficiency Reporting Value (MERV) of 13 or as required by the Authority Having Jurisdiction. Installed filters shall be clearly labeled by the manufacturer indicating the MERV rating.

Outside or return air for a heating or cooling air system shall not be taken from the following locations:

(1) Less than the separation distances to vents required by Section 802.6.1 and Section 802.8.

(2) Less than the separation distances required by Section 402.4.

(3) A hazardous or insanitary location, or a refrigeration machinery room as defined in this code.

(4) An area, the volume of which is less than 25 percent of the entire volume served by such system, unless there is a permanent opening to an area the volume of which is equal to 25 percent of the entire volume served.

Exception: Such openings where used for a heating or cooling air system in a dwelling unit shall be permitted to be reduced to not less than 50 percent of the required area, provided the balance of the required return air is taken from a room or hall having not less than three doors leading to other rooms served by the furnace.

(5) A closet, bathroom, toilet room, kitchen, garage, boiler room, furnace room, or unconditioned attic.

(6) Rooms or spaces containing a fuel-burning appliance therein. Where such room or space serves as source of return-air.

Exceptions:

(1) This shall not apply to fireplaces, fireplace appliances, residential cooking appliances, direct vent appliances, enclosed furnaces, and domestic-type clothes dryers installed within the room or space.

(2) This shall not apply to a gravity-type or listed vented wall heating or cooling air system.

(3) This shall not apply to a blower-type heating or cooling air system installed in accordance with the following requirements:

(a) Where the return air is taken from a room or space having a volume exceeding 1 cubic foot (0.03 m [3] ) for each 10 Btu/h (0.003 kW) fuel input rating of fuel-burning appliances therein.

(b) Not less than 75 percent of the supply air is discharged back into the same room or space.

(c) Return-air inlets shall not be located within 10 feet (3048 mm) from an appliance firebox or draft diverter in the same enclosed room or confined space.

dwelling unit shall not discharge into another dwelling unit through the heating or cooling air system.

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idential Air Filtration. In mechanically ventilated residen- tial buildings, air filters shall be provided to clean outdoor air and return air prior to its delivery to occupied spaces where specified in California Energy Code Sections 150.0(m)12 and 160.2(b). The air filters shall comply with California Energy Code requirements for labeling, ventilation system design and installation, air filter efficacy, and air filter pressure drop.

Water supply, sanitary drainage, and backflow protection shall be in accordance with the California Plumbing Code .

Piping, tubing, appliances, and appurtenances shall be supported in accordance with this code, the manufacturer’s installation instructions, and in accordance with the Authority Having Jurisdiction. Seismic restraints shall be in accordance with the building code.

sufficient strength to support the weight of the pipe or tubing and its contents. Piping or tubing shall be isolated from incompatible materials.

shall be supported at intervals not to exceed those shown in Table 313.3.

such a manner as to maintain its alignment and prevent sagging.

ground shall be laid on a firm bed for its entire length; where other support is otherwise provided, it shall be approved in accordance with Section 302.0.

smaller than those shown in Table 313.6.

TABLE 313.6

HANGER ROD SIZES

For SI units: 1 inch = 25.4 mm

straps or hooks at intervals not to exceed those shown in Table 1310.3.5.1.

systems (including hydronic systems) shall be balanced in accordance with one of the following methods:

TABLE 313.6

HANGER ROD SIZES

(1) AABC National Standards for Total System Balance

(2) ACCA Manual B

(3) ASHRAE 111

(4) NEBB Procedural Standards for Testing Adjusting Balancing of Environmental Systems

(5) SMACNA HVAC Systems Testing, Adjusting, and Balancing

prone regions that are within 1 mile (2 km) of the coastal mean high water line where the basic wind speed is 110 miles per hour (mi/h) (49.2 m/s) or more; or portions of hurricane-prone regions where the basic wind speed is 120 mi/h (53.6 m/s) or more; or Hawaii, shall be tested in accordance with Section 315.1.1 and Section 315.1.2.

315.1.1 Testing. Louvers that protect air intake or exhaust openings shall be tested in accordance with AMCA 550 for resistance to wind-driven rain.

315.1.2 Impact Resistance Test. Upon request by the Authority Having Jurisdiction, louvers protecting intake and exhaust ventilation ducts that are not fixed in the

open position and located within 30 feet (9144 mm) of the grade shall be tested for impact resistance in accordance with AMCA 540.

Structures.

walls shall be protected from breakage. Piping passing through or under cinders or other corrosive materials shall be protected from external corrosion in an approved manner. Approved provisions shall be made for expansion of hot water piping. Voids around piping or tubing passing through concrete floors on the ground shall be sealed.

the piping, tubing, or connections will not be subject to undue strains or stresses, and provisions shall be made for expansion, contraction, and structural settlement. No piping or tubing, unless designed and listed for such use, shall be directly embedded in concrete or masonry. No structural member shall be seriously weakened or impaired by cutting, notching, or otherwise as defined in the California Building Code or California Residential Code .

Piping or tubing subject to corrosion, erosion, or mechanical damage shall be protected in an approved manner.

or tubing shall be inspected and tested, and a visible void, damage, or imperfection to the pipe coating shall be repaired in an approved manner.

duct system penetrations of fire-resistance-rated walls, parti

For SI units: 1 inch = 25.4 mm

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tions, floors, floor/ceiling assemblies, roof/ceiling assemblies, or shaft enclosures shall be protected in accordance with the requirements of the California Building Code or California Residential Code .

or copper alloy piping or tubing, and ducts penetrating framing members to within 1 inch (25.4 mm) of the exposed framing shall be protected by steel nail plates not less than No. 18 gauge (0.0478 inches) (1.2141 mm) in thickness. The steel nail plate shall extend along the framing member not less than 1 [1] ⁄ 2 inches (38 mm) beyond the outside diameter of the pipe or tubing. Fuel gas piping shall be protected in accordance with Section 1310.4.3.

through concrete and masonry walls and concrete floors.

Exception: Sleeves shall not be required where openings are drilled or bored.

316.7.1 Building Loads. Piping or tubing through concrete or masonry walls shall not be subject to a load from building construction.

316.7.2 Exterior Walls. In exterior walls, annular space between sleeves and pipes or tubing shall be sealed and made watertight, as approved by the Authority Having Jurisdiction. A penetration through fire-resistive construction shall be in accordance with Section 316.5.

the space around the pipe or tubing completely sealed with an approved fire-resistive material in accordance with other codes.

A structural member weakened or impaired by cutting, notching, or otherwise shall be reinforced, repaired, or replaced so as to be left in a safe structural condition in accordance with the requirements of the California Building Code or California Residential Code .

Mechanical system shall be constructed in such a manner as to restrict rodents or vermin from entering a building by following the ductwork from the outside into the building.

have been made in walls, floors, or ceilings for the passage of ductwork or pipes, such openings shall be closed and protected by the installation of approved metal collars securely fastened to the adjoining structure.

building or structure, and paralleling the same, shall be located not less than 45 degrees (0.79 rad) from the bottom exterior edge of the footing, or as approved in accordance with Section 302.0.

be permitted to be done in yards, courts, or driveways of a building site. Where sufficient depth is available to permit, tunnels shall be permitted to be used between open-cut trenches.

Tunnels shall have a clear height of 2 feet (610 mm) above the pipe and shall be limited in length to one-half the depth of the trench, with a maximum length of 8 feet (2438 mm). Where pipes are driven, the drive pipe shall be not less than one size larger than the pipe to be laid.

the installation of a mechanical system or part thereof, within the walls of a building, shall be open trench work and shall be kept open until it has been inspected, tested, and accepted.

Excavations shall be completely backfilled as soon after inspection as practicable. Precaution shall be taken to ensure compactness of backfill around piping without damage to such piping. Trenches shall be backfilled in thin layers to 12 inches (305 mm) above the top of the piping with clean earth, which shall not contain stones, boulders, cinderfill, frozen earth, construction debris, or other materials that will damage or break the piping or cause corrosive action. Mechanical devices such as bulldozers, graders, etc., shall be permitted to then be used to complete backfill to grade. Fill shall be properly compacted. Precautions shall be taken to ensure permanent stability for pipe laid in filled or made ground.

ities regulated by OSHPD.

Note: This section has no corresponding provisions in the UMC. For the scope and authority of each state agency, refer to Chapter 1.

1224.4.1, 1225.2.1 and 1228.4.1.1 of the California Building Code.

ices Provided in Correctional Treatment Centers.

[OSHPD 1, 1R, 4 & 5]

319.1.1 Boilers shall have the capacity, based upon the rest ratings published by the Hydronics Institute or another acceptable national standard to supply the nor- mal operating requirements of all connected systems and equipment.

319.1.2 A minimum of two boilers shall be provided. The arrangement of boilers shall be based on the capacity and capability of a boiler or boilers to operate all sys- tems during-periods of breakdown or maintenance of any one boiler.

319.1.3 Boiler systems providing space heating shall be designed to maintain a minimum temperature of 60 ° F (15.6 ° C) in general patient areas and the temperatures specified in Table 4-A for sensitive areas during periods of breakdown or maintenance of any one boiler.

319.1.4 Boiler feed pumps, condensate return pumps, fuel oil pumps, and heating circulating pumps shall be connected and installed to provide standby service in the

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event of pump failure. Installation of duplex pumps or provision of a spare pump will meet this requirement. 319.1.5 At least two sources of heat (e.g. two pieces of equipment) shall be provided for supplying essential serv- ices such as sterilizers, hot water for dishwashing, and domestic hot water for minimum patient service, such as handwashing and baths. Booster heaters for dishwashing providing 125 ° F to 180 ° F (52 ° C to 82 ° C) water may be counted as the second source of heat for that service.

ate Care Facilities and Basic Services Provided in Correctional Treatment Centers. [OSHPD 2 & 4]

319.2.1 Boilers, if provided, shall accommodate Section 319.1.

319.2.2 Two or more interconnected water heaters are an acceptable means to provide two sources of heat for hot water (See Section 319.1.5).

ices Provided in Correctional Treatment Centers.

[OSHPD 1, 1R, 4 & 5]

320.1.1 The systems shall be designed to provide the temperatures and relative humidity for sensitive areas or rooms shown in Table 4-A. When outdoor humidity and internal moisture sources are not sufficient to meet the requirements of sensitive areas or rooms in Table 4-A, humidification shall be provided by means of the health- care facility air-handling systems. Temperature shall be individually controlled for each operating and delivery room. Burn unit patient rooms that require humidifiers to comply with the requirements of sensitive areas or rooms in Table 4-A shall be provided with individual humidity control. Humidifiers shall be of the dry steam or adiabatic atomizing type. Adiabatic atomizing humidi- fiers shall comply with the water treatment requirements in accordance with ASHRAE 170. Humidifiers shall be located within air handling systems or ductwork to avoid moisture accumulation in downstream components, including filters and insulation. 320.1.2 Heating systems shall be designed based on the “Heating DB 99.6%” column of the Climatic Design Data in ASHRAE Handbook-Fundamentals. The systems shall be thermostatically controlled with appropriate zoning to achieve the above conditions. 320.1.3 Cooling systems shall be designed based on the 0.4% columns of the four Annual Design Conditions titled Cooling, Evaporation, Dehumidification, and Enthalpy shown by the Climate Design Data in ASHRAE Handbook-Fundamentals. The systems shall be thermo- statically controlled with appropriate zoning to achieve the above conditions.

ate Care Facilities and Basic Services Provided in Correctional Treatment Centers. [OSHPD 2 & 4]

320.2.1 Systems shall accommodate the provisions of Sections 320.1.2 through 320.1.3.

320.2.2 Where air conditioning is provided, the system shall be thermostatically controlled in one or more zones.

Licensed Clinics. [OSHPD 3]

320.3.1 The system shall be designed to provide the tem- perature and humidities for sensitive areas for rooms shown in Table 4-A.

[OSHPD 1 & 4] Where telecommunications service entrance rooms, technology equipment centers, or technology distribu- tion rooms are provided in accordance with Section 1224.5 of the California Building Code, the following requirements shall apply: 320.4.1 Power for HVAC systems serving the room(s) shall be supplied by the Equipment Branch pursuant to the California Electrical Code. Where redundant systems are provided, only one shall be required to be supplied by the Equipment Branch. 320.4.2 Mechanical equipment or fixtures that are not directly related to the support of the room shall not be installed in or pass through the room. Exception: Unrelated ductwork may be installed and shall be not less than 10 feet (3048 mm) above the finished floor. 320.4.3 HVAC systems shall be provided to maintain environmental conditions recommended in ASHRAE’s Thermal Guidelines for Data Processing Environment and the requirements of the specific equipment installed. 320.4.4 Technology equipment centers shall have redun- dant cooling systems each of sufficient capacity to pro- vide required cooling during periods of breakdown or maintenance of either system. One system shall be non- hydronic and on essential power.

projects associated with provision of psychiatric services in acute psychiatric hospitals, general acute-care hospitals, and special treatment program service units in skilled nursing facilities, psychiatric, seclusion, and holding-patient rooms shall be designed with security diffusers, grilles, and registers.

3 (Surgical Clinics only) 4 & 5] During periods of power outages essential electrical power shall be provided for the following equipment:

ing equipment and fans necessary to maintain a minimum temperature of 60°F (15.6°) in patient areas which are not specified in Section 322.0.

the minimum temperatures listed in Table 4-A for sensitive areas specified in Section 322.0.

and humidity listed in Table 4-A for a minimum of one oper- ating room and other spaces as identified in the functional

program.

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listed in Section 322.0.

the positive and negative air balances as required in Table 4-A .

smoke dampers necessary for the normal operation of equip- ment required to have essential electrical power.

tective environment rooms.

gical Clinics) 4 & 5] The following are sensitive areas or

rooms:

(1) Operating room

(2) Hybrid operating room

(3) Cesarean operating room

(4) Delivery room

(5) Surgical Cystoscopy

(6) Class 3 imaging

(7) Cardiac catheterization lab

(8) Trauma/cardiac room

(9) Post-anesthesia care unit

(10)Intensive care

(11) Newborn intensive-care nursery unit

(12)Newborn nursery

(13)Burn unit

(14)Protective Environment Room

(15)Procedure room

(16)Class 2 imaging

(17)Gastrointestinal endoscopy procedure room

areas or rooms:

(1) Thermostats and humidistats shall be either locally reset- table and of the non-locking type or remotely resettable and of the locking type.

(2) Systems shall be capable of maintaining the rooms within the temperature range in Table 4-A during normal oper- ation. Lower or higher temperature shall be permitted when patients’ comfort and/or medical conditions require those conditions.

(3) The humidity ranges listed in Table 4-A are the minimum and maximum limits where control is specifically needed.

(4) Types of intensive care service spaces are listed in the California Building Code.

1R, 2, 4 & 5] Mechanical equipment schedules in the con- struction documents shall clearly indicate which equipment will be powered by essential power and which equipment includes the appropriate special seismic certifications.

[OSHPD 1, 1R, 2, 3, 4 & 5] The minimum horizontal sepa- ration distance between diesel-powered emergency electrical generator exhaust outlets and operable doors, windows and intake openings shall be 30 feet (9144 mm). The minimum horizontal distance from the generator exhaust to a property line shall be 15 feet (4572 mm) or per the requirements of the Authority Having Jurisdiction, whichever is greater.

tures. [OSHPD 2] Mechanical equipment required to main- tain a safe temperature for residents shall be powered by an alternate source of power per California Electrical Code Sec- tion 517.1. The safe temperature shall be between 71°F to 81°F (21.6°C to 27.2°C).

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TABLE 303.10.1 REDUCTION OF CLEARANCES WITH SPECIFIED FORMS OF PROTECTION [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]

For SI units: 1 inch = 25.4 mm

Notes:

1 Reduction of clearances from combustible materials shall not interfere with combustion air, draft hood clearance and relief, and accessibility of servicing. 2 All clearances shall be measured from the outer surface of the combustible material to the nearest point on the surface of the appliance, disregarding any intervening protection applied to the combustible material. 3 Spacers and ties shall be of noncombustible material. No spacer or tie shall be used directly opposite the appliance or connector. 4 Where all clearance reduction systems use a ventilated air space, adequate provision for air circulation shall be provided as described. [See Figure 303.10.1(2) and Figure 303.10.1(3)] 5 At least 1 inch (25.4 mm) shall be between clearance reduction systems and combustible walls and ceilings for reduction systems using a ventilated air space. 6 Where a wall protector is installed on a single flat wall away from corners, it shall have a minimum 1 inch (25.4 mm) air gap. To provide adequate air circulation, the bottom and top edges, or only the side and top edges, or all edges shall be left open. 7 Mineral wool batts (blanket or board) shall have a minimum density of 8 pounds per cubic foot (lb/ft 3 ) (128 kg/m 3 ) and a minimum melting point of 1500°F (816°C). 8 Insulation material used as part of a clearance reduction system shall have a thermal conductivity of 1.0 British thermal unit inch per hour square foot degree Fahrenheit [Btu•in/(h•ft [2] - °F)] [0.1W/(m•K)] or less. 9 At least 1 inch (25.4 mm) shall be between the appliance and the protector. The clearance between the appliance and the combustible surface shall not be reduced below that allowed in Table 303.10.1. 10 All clearances and thicknesses are minimum; larger clearances and thicknesses are acceptable. 11 Listed single-wall connectors shall be installed in accordance with the manufacturer’s installation instructions.

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Notes: 1 A – Equals the clearance with no protection specified in Table 802.7.3.3 and Table 904.3.2 and in the sections applying to various types of equipment. 2 B – Equals the reduced clearance permitted in accordance with Table 303.10.1. 3 The protection applied to the construction using combustible material shall extend far enough in each direction to make C equal to A.

FIGURE 303.10.1(1) 1, 2, 3 EXTENT OF PROTECTION NECESSARY TO REDUCE

CLEARANCES FROM GAS APPLIANCE OR VENT CONNECTORS

[NFPA 54: FIGURE 10.3.3.3(a)]

For SI units: 1 inch = 25.4 mm

FIGURE 303.10.1(3) MASONRY CLEARANCE REDUCTION SYSTEM

[NFPA 54: FIGURE 10.3.3.3(c)]

For SI units: 1 inch = 25.4 mm

Notes:

1 Masonry walls can be attached to combustible walls using wall ties.

2 Spacers shall not be used directly behind appliance or connector. FIGURE 303.10.1(2) WALL PROTECTOR CLEARANCE REDUCTION SYSTEM

[NFPA 54: FIGURE 10.3.3.3(b)]

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TABLE 313.3

HANGERS AND SUPPORTS

For SI unit: 1 inch = 25.4 mm, 1 foot = 304.8 mm

Notes: 1 Support adjacent to joint, not to exceed 18 inches (457 mm). 2 Brace not to exceed 40 feet (12 192 mm) intervals to prevent horizontal movement. 3 Support at each horizontal branch connection. 4 Hangers shall not be placed on the coupling. 5 Vertical water lines shall be permitted to be supported in accordance with recognized engineering principles with regard to expansion and contraction, where first approved by the Authority Having Jurisdiction.

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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE