Classification, wiring materials and interior finish (Detection, Lighting and Power)

Last updated October 22, 2026

Values this chapter turns on

min spacing of diffusers in rated corridors: 1.2 m; min spacing of diffusers in rated corridors
max area of each diffuser in a rated corridor: 1 m²; max area of each diffuser in a rated corridor
reach from a plenum where FT4 wiring is allowed: 9 m; reach from a plenum where FT4 wiring is allowed
max outside diameter, enclosed non-metallic raceway: 175 mm; max outside diameter, enclosed non-metallic raceway

Section 3.1. sets up everything else in Part 3. Classification decides which fire alarm, lighting and power rules apply. The combustibility rules decide which cables you may run where. The interior finish rules cover light diffusers and lenses. Finally, 3.1.20. keeps buildings clear of overhead power lines.

Classification and multiple occupancies

Every building or part is classified by major occupancy using Table 3.1.2.1. A building with several major occupancies is classified under all of them OBC Div. B 3.1.2.1.. Occupancies in the same Group (or Division, where the Group is divided) count as one major occupancy OBC Div. B 3.1.2.2..

Classification shortcuts that change the alarm and lighting rules:

Situation	Permitted classification	Article
Group B-3 suite, single housekeeping unit, sleeping for 10 or fewer, not more than 2 needing help to evacuate	Group C	3.1.2.5.
Restaurant designed for not more than 30 persons eating or drinking	Group E	3.1.2.7.

Major occupancies are separated by fire separations from Table 3.1.3.1. In a building of up to 3 storeys, up to two dwelling units with a Group E occupancy need not more than 1 h between them OBC Div. B 3.1.3.1.. Some combinations are banned outright OBC Div. B 3.1.3.2.:

Group F, Division 1 may not share a building with any Group A, B or C occupancy.
A Group F, Division 2 building may contain only one residential suite (live/work buildings excepted).
A building under 3.2.2.51. or 3.2.2.60. may not contain a retirement home.

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Wires, cables, raceways and noncombustible construction

"Noncombustible" means passing the CAN/ULC-S114 test Div. A. Combustible construction may use combustible materials freely OBC Div. B 3.1.4.1., but cables with combustible jackets still have limits.

Location	Cable rule
Combustible construction, general	FT1 (no flame or burning beyond 1 min), or enclosed in a noncombustible raceway, masonry wall, concrete slab or qualifying non-metallic raceway 3.1.4.3.(1)
Combustible construction, plenum, voice/sound/data cables	FT6 limits: 1.5 m horizontal flame distance, smoke density 0.15 average and 0.5 peak 3.1.4.3.(2)
Noncombustible construction, general	FT4 (vertical char not over 1.5 m), or enclosed, or in a 1 h service room, or service-entry communication cable not over 3 m long 3.1.5.21.(1)
Noncombustible construction, plenum	FT6 unless in totally enclosed noncombustible raceways 3.1.5.21.(2)

Where noncombustible raceways are used in a plenum, exposed wiring in the plenum, or extending up to 9 m from it, may be FT4 OBC Div. B 3.1.5.21.(3).

Fire alarm cables in plenums are exempt from the FT6 rule in both construction types OBC Div. B 3.1.4.3.(4). In noncombustible construction they are also exempt from the 9 m FT4 rule OBC Div. B 3.1.5.21.(4). Other noncombustible-construction allowances:

totally enclosed non-metallic raceways up to 175 mm outside diameter, meeting an FT4-type test that depends on the cables inside, and the FT6 limits where they run in a plenum OBC Div. B 3.1.5.23.,
combustible travelling cables on elevating devices OBC Div. B 3.1.5.22.,
cables under a computer room raised floor, if FT1 rated OBC Div. B 3.1.5.25.,
a combustible solar collector system above the roof OBC Div. B 3.1.5.28..

Totally enclosed non-metallic raceways in a plenum of a combustible building must meet the FT4 requirement of Clause 3.1.5.23.(1)(a) OBC Div. B 3.1.4.4..

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Interior finish, flame spread and light diffusers

Interior finish includes lighting elements such as diffusers and lenses that form part of the finished ceiling OBC Div. B 3.1.13.1.. Walls and ceilings are generally limited to a flame-spread rating of 150, with stricter values in Table 3.1.13.2. Doors outside Group A, Division 1 may go to 200, and doors within a dwelling unit are exempt OBC Div. B 3.1.13.2..

Light diffusers and lenses that exceed these limits (outside Group A, Division 1) are allowed when they OBC Div. B 3.1.13.4.:

have a flame-spread rating of 250 or less and a smoke developed classification of 600 or less (CAN/ULC-S102.2),
fall out of the test apparatus before igniting (CAN/ULC-S102.3),
are free to fall (nothing built beneath them), and
in a fire-separated corridor or exit shaft, are each not over 1 m² and at least 1.2 m apart.

High buildings. Buildings under 3.2.6. must also meet Table 3.1.13.7. If the building is sprinklered, the table values are waived, except in Group B buildings and in elevator cars. Elevator car walls and ceilings stay at 75 flame spread and 450 smoke developed OBC Div. B 3.1.13.7..

Worked example

A designer wants plastic lens panels in a rated corridor of an office building. Each panel is 0.8 m² and passes S102.2 at 230 flame spread and 500 smoke developed, and it drops in the S102.3 test.

Ratings: 230 is within 250 and 500 is within 600. Pass.
Size: 0.8 m² is within 1 m². Pass.
Spacing: the layout shows 1.0 m between panels. Fail. They must be at least 1.2 m apart. Respace the panels and the design complies.

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Above ground electrical conductors

Do not build under existing overhead conductors. Horizontal clearance is measured from the maximum conductor swing to the building, including balconies, fire escapes and flat roofs OBC Div. B 3.1.20.1.:

Voltage	Minimum clearance
750 V or less	1 m (except where connecting to the building)
Over 750 V to 46 kV	3 m
Over 46 kV to 69 kV	3.7 m
Over 69 kV	Per CAN/CSA-C22.3 No. 1

If the swing of a privately owned line is unknown, assume 1.8 m. Part 9 buildings follow the same Article through 9.1.1.5.

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Common traps

Requiring FT6 on fire alarm signal cables in a plenum. They are exempt.
Applying the noncombustible FT4 rule to combustible construction, where FT1 is the baseline.
Assuming the high building finish table is waived in elevator cars of a sprinklered building. It is not.
Mixing up the diffuser area limit (1 m²) with the spacing (1.2 m).
Measuring overhead line clearance from the pole. It is measured from the maximum conductor swing.

Chapter review

Chapter at a glance

One line per section: the idea to carry into the exam. Then the answers that most often catch candidates out.

Chapter at a glance: the key idea in each section
Section	Key idea
Classification and multiple occupancies	Every building or part is classified by major occupancy using Table 3.1.2.1. A building with several major occupancies is classified under all of them.
Wires, cables, raceways and noncombustible construction	"Noncombustible" means passing the CAN/ULC-S114 test.
Interior finish, flame spread and light diffusers	Interior finish includes lighting elements such as diffusers and lenses that form part of the finished ceiling.
Above ground electrical conductors	Do not build under existing overhead conductors.

Classification and multiple occupancies
Every building or part is classified by major occupancy using Table 3.1.2.1. A building with several major occupancies is classified under all of them.
Wires, cables, raceways and noncombustible construction
"Noncombustible" means passing the CAN/ULC-S114 test.
Interior finish, flame spread and light diffusers
Interior finish includes lighting elements such as diffusers and lenses that form part of the finished ceiling.
Above ground electrical conductors
Do not build under existing overhead conductors.

Usual exam traps

Requiring FT6 on fire alarm signal cables in a plenum. They are exempt.
Applying the noncombustible FT4 rule to combustible construction, where FT1 is the baseline.
Assuming the high building finish table is waived in elevator cars of a sprinklered building. It is not.
Mixing up the diffuser area limit (1 m²) with the spacing (1.2 m).
Measuring overhead line clearance from the pole. It is measured from the maximum conductor swing.

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Questions on Classification, wiring materials and interior finish (3.1), in the exam format, every answer explained and cited to its article. Sign in to start; a free account gets the free questions.

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Code cited in this chapter

Based on the official 2024 Building Code Compendium on ontario.ca.

OBC Div. B 3.1.2.1. Classification of Buildings
(1)Except as permitted by Articles 3.1.2.3. to 3.1.2.7., every building or part thereof shall be classified according to its major occupancy as belonging to one of the Groups or Divisions described in Table 3.1.2.1. (See Note A-3.1.2.1.(1))
(2)A building intended for use by more than one major occupancy shall be classified according to all major occupancies for which it is used or intended to be used.
Open OBC Div. B 3.1.2.1. in the code viewer
OBC Div. B 3.1.2.2. Occupancies of the Same Classification
(1)Any building is deemed to be occupied by a single major occupancy, notwithstanding its use for more than one major occupancy, provided that all occupancies are classified as belonging to the same Group classification or, where the Group is divided into Divisions, as belonging to the same Division classification described in Table 3.1.2.1.
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OBC Div. B 3.1.2.5. Group B, Division 3 Occupancies
(1)Group B, Division 3 occupancies are permitted to be classified as Group C major occupancies within the application of Part 3 provided
(a)the occupants live as a single housekeeping unit in a suite with sleeping accommodation for not more than 10 persons, and
(b)not more than two occupants require assistance in evacuation in case of an emergency.
Open OBC Div. B 3.1.2.5. in the code viewer
OBC Div. B 3.1.2.7. Restaurants
(1)A restaurant is permitted to be classified as a Group E major occupancy within the application of Part 3 provided the restaurant is designed to accommodate not more than 30 persons consuming food or drink.
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OBC Div. B 3.1.3.1. Separation of Major Occupancies
(1)Except as permitted by Sentences (2) and (3), major occupancies shall be separated from adjoining major occupancies by fire separations having fire-resistance ratings conforming to Table 3.1.3.1.
(2)In a building not more than 3 storeys in building height, if not more than two dwelling units are contained together with a Group E major occupancy, the fire-resistance rating of the fire separation between the two major occupancies need not be more than 1 h.
(3)In a building conforming to the requirements of Articles 3.2.8.2. to 3.2.8.8., the requirements of Sentence (1) for fire separations between major occupancies do not apply at the vertical plane around the perimeter of an opening through the horizontal fire separation.
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OBC Div. B 3.1.3.2. Prohibition of Occupancy Combinations
(1)No major occupancy of Group F, Division 1 shall be contained within a building with any occupancy classified as Group A, B or C.
(2)Except as provided in Sentence (4) and Sentence 3.10.2.4.(9), not more than one suite of residential occupancy shall be contained within a building classified as a Group F, Division 2 major occupancy.
(3)A sleeping room or sleeping area shall not open directly into a room or area where food is intended to be stored, prepared, processed, distributed, served, sold or offered for sale. (See Note A-3.1.3.2.(3))
(4)A Group F, Division 2 major occupancy is permitted in a building containing only live/work units if the occupancy is for the exclusive use of the occupants of the live/work units.
(5)A building within the scope of Article 3.2.2.51. or 3.2.2.60. shall not contain a retirement home.
Open OBC Div. B 3.1.3.2. in the code viewer
OBC Div. A 1.4.1.2.(1) Noncombustible
Noncombustible means that a material meets the acceptance criteria of CAN/ULC-S114, "Standard Method of Test for Determination of Non-Combustibility in Building Materials."
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. B 3.1.4.1. Combustible Materials Permitted
(1)A building permitted to be of combustible construction is permitted to be constructed of combustible materials, with or without noncombustible components. (See Note A-3.1.4.1.(1))
Open OBC Div. B 3.1.4.1. in the code viewer

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OBC Div. B 3.1.4.3. Wires and Cables
(1)Except as required by Sentence (2), optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes installed in a building permitted to be of combustible construction shall
(a)not convey flame or continue to burn for more than 1 min when tested in conformance with the Vertical Flame Test (FT1 rating) in CSA C22.2 No. 0.3, "Test Methods for Electrical Wires and Cables," or
(b)be located in
(i)totally enclosed noncombustible raceways, (See Note A-3.1.4.3.(1)(b)(i))
(ii)masonry walls,
(iii)concrete slabs, or
(iv)totally enclosed non-metallic raceways conforming to Clause 3.1.5.23.(1)(b). (See Note A-3.1.4.3.(1)) (See also Sentence 3.6.4.3.(1))
(2)Except as permitted in Sentences (3) and (4), optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes that are used for the transmission of voice, sound or data and are installed in a plenum in a building permitted to be of combustible construction shall exhibit the following characteristics when tested in conformance with CAN/ULC-S102.4, "Standard Method of Test for Fire and Smoke Characteristics of Electrical Wiring, Cables and Non-Metallic Raceways," (FT6 rating):
(a)a horizontal flame distance of not more than 1.5 m,
(b)an average optical smoke density of not more than 0.15, and
(c)a peak optical smoke density of not more than 0.5.
(3)Except as permitted in Sentence (4), where totally enclosed noncombustible raceways are used in a plenum, exposed components of wiring systems with combustible insulation, jackets or sheathes, including optical fibre cables and electrical wires and cables that are used for the transmission of voice, sound or data, that are installed in the plenum or that extend not more than 9 m from the plenum, including drop down to the floor level, are permitted, provided they exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test-Cables in Cable Trays (FT4 rating) in CSA C22.2 No. 0.3, "Test Methods for Electrical Wires and Cables."
(4)Cables or wires within plenums that are used for the transmission of signals in fire alarm systems need not comply with the requirements of Sentence (2).
Open OBC Div. B 3.1.4.3. in the code viewer
OBC Div. B 3.1.5.21. Wires and Cables
(1)Except as permitted by Sentence (2) and Articles 3.1.5.22. and 3.1.5.25., optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes are permitted in a building required to be of noncombustible construction, provided
(a)the wires and cables exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test-Cables in Cable Trays (FT4 rating) in CSA C22.2 No. 0.3, "Test methods for electrical wires and cables,"
(b)the wires and cables are located in
(i)totally enclosed noncombustible raceways, (See Note A-3.1.4.3.(1)(b)(i))
(ii)masonry walls.
(iii)concrete slabs,
(iv)a service room separated from the remainder of the building by a fire separation having a fire-resistance rating not less than 1 h, or
(v)totally enclosed non-metallic raceways conforming to Clause 3.1.5.23.(1)(b), or
(c)the wires and cables are communication cables used at the service entry to a building and are not more than 3 m long. (See Note A-3.1.5.21.(1))
(2)Except as permitted in Sentences (3) and (4), optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes that are used for the transmission of voice, sound or data and are not located in totally enclosed noncombustible raceways are permitted to be installed in a plenum in a building required to be of noncombustible construction, provided the wires and cables exhibit a horizontal flame distance of not more than 1.5 m, an average optical smoke density of not more than 0.15, and a peak optical smoke density of not more than 0.5 when tested in conformance with CAN/ULC-S102.4, "Standard Method of Test for Fire and Smoke Characteristics of Electrical Wiring, Cables and Non-Metallic Raceways," (FT6 rating).
(3)Except as permitted in Sentence (4), where totally enclosed noncombustible raceways are used in a plenum, exposed components of wiring systems with combustible insulation, jackets or sheathes, including optical fibre cables and electrical wires and cables that are used for the transmission of voice, sound or data, that are installed in the plenum or that extend not more than 9 m from the plenum including drop down to the floor level, are permitted provided they exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test-Cables in Cable Trays (FT4 rating) in CSA C22.2 No. 0.3, "Test methods for electrical wires and cables."
(4)Cables or wires within plenums that are used for the transmission of signals in fire alarm systems need not comply with the requirements of Sentences (2) and (3).
Open OBC Div. B 3.1.5.21. in the code viewer
OBC Div. B 3.1.5.23. Non-metallic Raceways
(1)Except as required in Sentence (2), subject to the limits on the size of elements that penetrate fire separations when complying with Article 3.1.9.2., within a fire compartment of a building required to be of noncombustible construction, totally enclosed non-metallic raceways not more than 175 mm in outside diameter, or of an equivalent rectangular area, are permitted to be used to enclose optical fibre cables and electrical wires and cables, provided
(a)where the wires and cables in the raceways meet or exceed the requirements of Clause 3.1.5.21.(1)(a), the non-metallic raceways meet the requirements for at least an FT4 rating in,
(i)CAN/CSA-C22.2 No. 262, "Optical Fiber Cable and Communication Cable Raceway Systems," or
(ii)CAN/ULC-S143, "Standard Method of Fire Tests for Non-Metallic Electrical and Optical Fibre Cable Raceway Systems," and
(b)where the wires and cables in the raceways do not meet or exceed the requirements of Clause 3.1.5.21.(1)(a), the non-metallic raceways exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test (FT4)-conduit or Tubing on Cable Tray in Clause 6.16 of CSA C22.2 No. 211.0, "General Requirements and Methods of Testing for Nonmetallic Conduit."
(2)Totally enclosed non-metallic raceways used in a plenum in a building required to be of noncombustible construction shall exhibit a horizontal flame distance of not more than 1.5 m, an average optical smoke density of not more than 0.15, and a peak optical smoke density of not more than 0.5 when tested in conformance with CAN/ULC-S102.4, "Standard Method of Test for Fire and Smoke Characteristics of Electrical Wiring, Cables and Non-Metallic Raceways," (FT6 rating).
Open OBC Div. B 3.1.5.23. in the code viewer
OBC Div. B 3.1.5.22. Combustible Travelling Cables for Elevators
(1)Combustible travelling cables are permitted on elevating devices in a building required to be of noncombustible construction.
Open OBC Div. B 3.1.5.22. in the code viewer
OBC Div. B 3.1.5.25. Wires in Computer Room Floors
(1)Optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes, located in the space below a raised floor in a computer room, are permitted in a building required to be of noncombustible construction provided they do not convey flame or continue to burn for more than 1 min when tested in conformance with the Vertical Flame Test in Clause 4.11.1. of CSA C22.2 No. 0.3, "Test methods for electrical wires and cables," (FT1 Rating).
(2)The requirement in Sentence (1) is considered to be met where the wires and cables
(a)exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test-Cables in Cabletrough in Clause 4.11.4. of CSA C22.2 No. 0.3, "Test methods for electrical wires and cables," (FT4 Rating), or
(b)exhibit a flame-spread of not more than 1.5 m, a smoke density of not more than 0.5 at peak optical density and a smoke density not more than 0.15 at average optical density when tested in conformance with the Flame and Smoke Test in the Appendix to CSA C22.2 No. 0.3, "Test methods for electrical wires and cables," (FT6 Rating).
Open OBC Div. B 3.1.5.25. in the code viewer
OBC Div. B 3.1.5.28. Combustible Solar Collector Systems
(1)A combustible solar collector system is permitted to be installed above the roof of a building required to be of noncombustible construction.
Open OBC Div. B 3.1.5.28. in the code viewer
OBC Div. B 3.1.4.4. Non-metallic Raceways
(1)Totally enclosed non-metallic raceways used in a plenum in a building permitted to be of combustible construction shall meet the requirements of Clause 3.1.5.23.(1)(a).
Open OBC Div. B 3.1.4.4. in the code viewer
OBC Div. B 3.1.13.1. Interior Finishes, Furnishings and Decorative Materials
(1)Except as otherwise provided in this Subsection, interior finishes, furnishings and decorative materials shall conform to
(a)the Fire Code made under the Fire Protection and Prevention Act, 1997, or
(b)Section 2.3. of Division B of the CCBFC NRC-CONST-56437E, "National Fire Code of Canada", in the absence of regulations referred to in Clause (a).
(2)Interior finish material shall include any material that forms part of the interior surface of a floor, wall, partition or ceiling, including
(a)interior cladding of plaster, wood or tile,
(b)surfacing of fabric, paint, plastic, veneer or wallpaper,
(c)doors, windows and trim,
(d)lighting elements, such as light diffusers and lenses forming part of the finished surface of the ceiling, and
(e)carpet material that overlies a floor that is not intended as the finished floor.
Open OBC Div. B 3.1.13.1. in the code viewer
OBC Div. B 3.1.13.2. Flame-Spread Rating
(1)Except as otherwise required or permitted by this Subsection, the flame-spread rating of interior wall and ceiling finishes, including glazing and skylights, shall be not more than 150 and shall conform to Table 3.1.13.2.
(2)Except as permitted by Sentence (3), doors, other than those in Group A, Division 1 occupancies, need not conform to Sentence (1) provided they have a flame-spread rating not more than 200. (See Note A-3.1.13.2.(2))
(3)Doors within a dwelling unit need not conform to Sentences (1) and (2).
(4)Up to 10% of the total wall area and 10% of the total ceiling area of a wall or ceiling finish that is required by Sentence (1) to have a flame-spread rating less than 150 is permitted to have a flame-spread rating not more than 150, except that up to 25% of the total wall area of lobbies described in Sentence 3.4.4.2.(2) is permitted to have a flame-spread rating not more than 150.
(5)Except in the case of Group A, Division 1 occupancies, combustible doors, skylights, glazing and light diffusers and lenses shall not be considered in the calculation of wall and ceiling areas described in Sentence (4).
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OBC Div. B 3.1.13.4. Light Diffusers and Lenses
(1)The flame-spread rating of combustible light diffusers and lenses in all occupancies other than Group A, Division 1 is permitted to be more than the flame-spread rating limits required elsewhere in this Subsection, provided the light diffusers and lenses
(a)have a flame-spread rating not more than 250 and a smoke developed classification not more than 600 when tested in conformance with CAN/ULC-S102.2, "Standard Method of Test for Surface Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies,"
(b)fall to the bottom of the test apparatus before igniting when tested in conformance with CAN/ULC-S102.3, "Standard Method of Fire Test of Light Diffusers and Lenses,"
(c)are not prevented from falling from the ceiling by construction located beneath the elements, and
(d)are not used in a corridor that is required to be separated from the remainder of the building by a fire separation or in an exit shaft unless individual diffusers or lenses are not more than 1 m² in area and are not less than 1.2 m apart.
Open OBC Div. B 3.1.13.4. in the code viewer
OBC Div. B 3.1.13.7. High Buildings
(1)Except as permitted by Sentences (2) to (4), the interior wall, ceiling and floor finishes in a building regulated by the provisions of Subsection 3.2.6. shall conform to the flame-spread rating requirements in Articles 3.1.13.2. to 3.1.13.6. and 3.1.13.11. and to the flame-spread rating and smoke developed classification values in Table 3.1.13.7.
(2)Except for a building of Group B major occupancy and elevator cars, the flame-spread rating and smoke developed classification of interior wall, floor and ceiling finishes need not conform to the values in Table 3.1.13.7., provided the building is sprinklered.
(3)Trim and millwork in an exit stairway, a vestibule to an exit stairway, a lobby described in Sentence 3.4.4.2.(2), or a corridor not within a suite need not conform to the flame-spread rating and smoke developed classification requirements of Sentence (1), provided they have
(a)a flame-spread rating not more than 150,
(b)a smoke developed classification not more than 300, and
(c)an aggregate area not more than 10% of the area of the wall or ceiling on which they occur.
(4)A door serving an exit stairway, a vestibule to an exit stairway, a lobby described in Sentence 3.4.4.2.(2), or a corridor not within a suite need not conform to the flame-spread rating and smoke developed classification requirements of Sentence (1) provided
(a)it has a flame-spread rating not more than 200,
(b)it has a smoke developed classification not more than 300, and
(c)the aggregate area of all doors is not more than 10% of the area of the wall in which they are located.
(5)Except as permitted in Sentences (6) to (8), plumbing fixtures in a building regulated by the provisions of Subsection 3.2.6. shall have a smoke developed classification not more than 300.
(6)A plumbing fixture that is not located in a Group B occupancy need not comply with Sentence (5) if the building is sprinklered throughout.
(7)A plumbing fixture may have a smoke developed classification more than 300 but not more than 500 if,
(a)it is in a room where the wall surfaces have a smoke developed classification not more than 200, and
(b)it is located in,
(i)a Group C occupancy, or
(ii)a Group B occupancy and the building is sprinklered throughout.
(8)A therapeutic bathing system in a Group B occupancy need not comply with Sentence (5) if the room in which it is located.
(a)does not open directly into patients' or residents' sleeping rooms, and
(b)is sprinklered.
Open OBC Div. B 3.1.13.7. in the code viewer
OBC Div. B 3.1.20.1. Clearance to Buildings
(1)A building shall not be located beneath existing above ground electrical conductors.
(2)The horizontal clearance measured from the maximum conductor swing to the building, including balconies, fire escapes, flat roofs or other accessible projections beyond the face of the building, shall,
(a)be not less than 1 m, for electrical conductors carrying voltages 750 V or less, except where necessary to connect to the electrical wiring of the building,
(b)be not less than 3 m, for electrical conductors carrying voltages greater than 750 V but not exceeding 46 kV,
(c)be not less than 3.7 m, for electrical conductors carrying voltages greater than 46 kV but not exceeding 69 kV, or
(d)conform to the requirements of CAN/CSA-C22.3 No.1, "Overhead Systems," for electrical conductors carrying voltages greater than 69 kV.
(3)Where the swing of an above ground electrical conductor not owned or operated by an electrical supply authority is not known, a swing of not less than 1.8 m shall be used.
(4)Sentences (1) to (3) do not apply to a building containing electrical equipment and electrical installations used exclusively in the generation, transformation or transmission of electrical power or energy intended for sale or distribution to the public.
Open OBC Div. B 3.1.20.1. in the code viewer