Code structure and Part 3 fire-related plumbing items (Plumbing

Last updated October 22, 2026

Values this chapter turns on

firestop test pressure, plastic DWV over 3 storeys: 50 Pa; firestop test pressure, plastic DWV over 3 storeys
building height above which that DWV test applies: 3 storeys; building height above which that DWV test applies
max horizontal run of a concealed wall space: 20 m; max horizontal run of a concealed wall space
max chlorine gas pipe through a pool room wall: 25 mm; max chlorine gas pipe through a pool room wall

Plumbing - All Buildings starts where every technical exam starts: how the Code is organized, where definitions live, and how compliance works. Then it moves into Part 3, because pipes in a large building pass through fire separations, shafts and exits. A plumbing inspector on a mid-rise job needs to know when plastic pipe is allowed, how a penetration is sealed, and what may share a shaft with a refuse chute. This chapter covers those items. The House version of this exam touches some of them; here they carry more weight because Part 3 buildings are the norm.

How the Code applies

The Code applies to the construction, demolition, change of use and occupancy of buildings, whether site-built or factory-built (OBC Div. A 1.1.1.1.). Parts 7 and 12 of Division B apply to all buildings, subject to the existing building rules (OBC Div. A 1.3.3.1.). That is why there is one plumbing Part for a cottage and a hospital alike; size and occupancy change the numbers, not the Part.

Compliance is reached in one of two ways (OBC Div. A 1.2.1.1.):

Route	What it means
Acceptable solution	Meet the requirements stated in Parts 2 to 12 of Division B
Alternative solution	Show at least the same level of performance as the acceptable solution, for the objectives and functional statements attributed to it in SA-1

Used fixtures and equipment may be reinstalled if they meet the Code requirements for new materials and are satisfactory for their use (OBC Div. A 1.2.2.3.).

Firewalls and plumbing. A firewall normally splits a building into separate buildings for Code purposes. Div. A 1.3.3.4.(1) lists three exceptions, and one of them is "a plumbing system interconnected through a firewall" (OBC Div. A 1.3.3.4.). So a single plumbing system serving both sides is treated as one system.

Climatic data. Design values come from MMAH Supplementary Standard SB-1, and the outside winter design temperature is the January 2.5% value (OBC Div. B 1.1.3.1.).

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Definitions you will use

Definitions are in Div. A 1.4.1.2. A few that plumbing questions lean on:

Fixture: a device that discharges sewage or clear water waste, and the definition expressly includes a floor drain (OBC Div. A 1.4.1.2.).
Sanitary unit: a water closet, urinal, bidet or bedpan washer (OBC Div. A 1.4.1.2.). Lavatories and showers are not sanitary units.
Public use and private use: public use fixtures are those whose use is unrestricted, such as in general washrooms of schools and hotels; private use covers residences and private hotel bathrooms (public use, private use). Several Part 7 sizing values differ between the two.
Vertical service space: a shaft for services, including refuse and linen chutes (OBC Div. A 1.4.1.2.).

Objectives and functional statements

Division A Part 2 lists objectives and Part 3 lists functional statements (OBC Div. A 2.2.1.1., OBC Div. A 3.2.1.1.). SA-1 attributes them to each acceptable solution. The ones that show up most often for plumbing:

Code	Short meaning
OH2	Sanitation: illness from waste, contaminated water, poor hygiene facilities
OP5	Damage to the building from leaking service water or sewage
OR1	Conservation of water and energy
OE2	Release of contaminants into water and soil
F46	Minimize risk of contaminating potable water
F70 / F71 / F72	Provide potable water / hygiene facilities / sanitary waste disposal
F81	Minimize malfunction, damage, tampering, misuse

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Combustible piping and fixtures in noncombustible buildings

Part 3 buildings are often required to be of noncombustible construction, yet plastic DWV and water piping is common. OBC Div. B 3.1.5.19. allows combustible piping in such a building if, where it is not concealed in a wall or concrete floor slab, it has a flame-spread rating not more than 25, and in a high building (Subsection 3.2.6.) also a smoke developed classification not more than 50. Combustible sprinkler piping is allowed within a sprinklered floor area.

Polypropylene DWV for highly corrosive waste, and piping for distilled or dialyzed water, is allowed in laboratory and hospital facilities if the building is sprinklered throughout, the piping is not in a vertical shaft, and fire separation penetrations use an FT rated firestop tested with a 50 Pa pressure differential.

Combustible plumbing fixtures are allowed if their flame-spread and smoke values do not exceed those allowed for the wall surface of the room (OBC Div. B 3.1.5.20.). Pool and spa parts such as main drains, piping, skimmers and return inlets may be combustible (OBC Div. B 3.1.5.26.).

Fixture finishes. In a residential suite bathroom, plumbing fixtures have a flame-spread limit of 200 (OBC Div. B 3.1.13.3.). In a high building, fixtures are limited to a smoke developed classification of 300, but a fixture outside a Group B occupancy is exempt if the building is sprinklered throughout, and up to 500 is allowed in some Group C and sprinklered Group B rooms (OBC Div. B 3.1.13.7.).

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Firestops and penetrations

Pipes may penetrate a fire separation if sealed with a firestop meeting OBC Div. B 3.1.9.1.(1), that is an F rating not less than the separation's required rating, or cast in place for steel, ferrous, copper, concrete or masonry items (OBC Div. B 3.1.9.2.). Firewalls and certain horizontal separations need an FT rating instead.

Combustible piping has its own Article, OBC Div. B 3.1.9.4.:

Piping	Rule for penetrating a rated separation
Combustible sprinkler piping	Allowed if both fire compartments are sprinklered
Combustible water distribution piping	Allowed with an F rated firestop
Combustible DWV, building up to 3 storeys	F rated firestop; not in a vertical service space
Combustible DWV, building over 3 storeys	F rating tested at 50 Pa differential; not in a vertical service space
Central vacuum piping	Same as combustible DWV
Chlorine gas piping, max 25 mm, pool or spa room	Allowed with an F rated firestop

Fire blocks. Concealed wall spaces need fire blocks at each floor, at rated ceilings, and so no space exceeds 20 m horizontally or 3 m vertically (OBC Div. B 3.1.11.2.). Worked example: a 46 m long concealed space needs at least 3 pieces (20 + 20 + 6), so 2 intermediate fire blocks. Where pipes pass through fire blocks, the penetration is sealed with a firestop (OBC Div. B 3.1.11.7.).

Plenums. A ceiling space used as a plenum must meet OBC Div. B 3.6.4.3.: materials in it generally limited to a flame-spread rating of 25 and smoke developed classification of 50, with listed exceptions for some cables and raceways. Combustible pipe in a return-air ceiling is a common inspection issue.

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Exits, shafts and chutes

An exit's fire separation may have only the openings listed in OBC Div. B 3.4.4.4.: standpipe and sprinkler piping, and noncombustible piping that serves only the exit, among others. Washrooms and service rooms may not open directly into an exit.

Vertical service spaces need fire separations rated per Table 3.6.3.1., closed at the top and bottom if they do not run through (OBC Div. B 3.6.3.1.).

Linen and refuse chutes (OBC Div. B 3.6.3.3.) matter to plumbers in three ways:

Item	Requirement
Other services in the chute shaft	Only noncombustible DWV or noncombustible water piping
Refuse chute top	Spray equipment for washing down
Refuse discharge room or bin	Water connection and floor drain for washing down; 2 h separation

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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
How the Code applies	The Code applies to the construction, demolition, change of use and occupancy of buildings, whether site-built or factory-built.
Objectives and functional statements	Division A Part 2 lists objectives and Part 3 lists functional statements.
Combustible piping and fixtures in noncombustible buildings	Part 3 buildings are often required to be of noncombustible construction, yet plastic DWV and water piping is common.
Firestops and penetrations	Pipes may penetrate a fire separation if sealed with a firestop meeting, that is an F rating not less than the separation's required rating, or cast in place for steel, ferrous…
Exits, shafts and chutes	An exit's fire separation may have only the openings listed in: standpipe and sprinkler piping, and noncombustible piping that serves only the exit, among others.

How the Code applies
The Code applies to the construction, demolition, change of use and occupancy of buildings, whether site-built or factory-built.
Objectives and functional statements
Division A Part 2 lists objectives and Part 3 lists functional statements.
Combustible piping and fixtures in noncombustible buildings
Part 3 buildings are often required to be of noncombustible construction, yet plastic DWV and water piping is common.
Firestops and penetrations
Pipes may penetrate a fire separation if sealed with a firestop meeting, that is an F rating not less than the separation's required rating, or cast in place for steel, ferrous…
Exits, shafts and chutes
An exit's fire separation may have only the openings listed in: standpipe and sprinkler piping, and noncombustible piping that serves only the exit, among others.

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Questions on Code structure and Part 3 fire-related plumbing items, 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. A 1.1.1.1. Application of this Code
(1)This Code applies to the construction, demolition, change of use and occupancy of buildings.
(2)This Code applies to both site-built and factory-constructed buildings. (See Note A-1.1.1.1.(2))
Open OBC Div. A 1.1.1.1. in the code viewer
OBC Div. A 1.3.3.1. Application of Parts 1, 7 and 12
(1)Part 1 of Division B applies to all buildings covered in this Code. (See Article 1.1.1.1.)
(2)Subject to Article 1.3.3.3B., Parts 7 and 12 of Division B apply to all buildings covered in this Code.
Open OBC Div. A 1.3.3.1. in the code viewer
OBC Div. A 1.2.1.1. Compliance with this Code
(1)Compliance with this Code shall be achieved by
(a)complying with the applicable acceptable solutions in Division B (See Note A-1.2.1.1.(1)(a)), or
(b)using alternative solutions that will achieve at least the minimum level of performance required by the applicable acceptable solutions in respect of the objectives and functional statements attributed to the applicable acceptable solutions in Ministry of Municipal Affairs and Housing (MMAH) Supplementary Standard SA-1, "Objectives and Functional Statements Attributed to the Acceptable Solutions." (See Note A-1.2.1.1.(1)(b))
(2)For the purposes of Clause (1)(b), the level of performance in respect of a functional statement refers to the performance of the functional statement as it relates to the objective with which it is associated in MMAH Supplementary Standard SA-1, "Objectives and Functional Statements Attributed to the Acceptable Solutions."
Open OBC Div. A 1.2.1.1. in the code viewer
OBC Div. A 1.2.2.3. Used Materials, Appliances and Equipment
(1)Unless otherwise specified, recycled materials in building products may be used, and used materials, appliances and equipment are permitted to be reused when they meet the requirements of this Code for new materials and are satisfactory for the intended use.
Open OBC Div. A 1.2.2.3. in the code viewer
OBC Div. A 1.3.3.4. Building Size Determination
(1)Where a firewall divides a building, each portion of the building that is divided shall be considered as a separate building, except for the purposes of
(a)a determination of gross area in Section 1.2. of Division C,
(b)a fire alarm and detection system in Sentence 3.2.4.2.(1) of Division B or Article 9.10.18.1. of Division B, and
(c)a plumbing system interconnected through a firewall.
(2)Except as permitted in Sentence (3), where portions of a building are completely separated by a vertical fire separation that has a fire-resistance rating of not less than 1 h and extends through all storeys and service spaces of the separated portions, each separated portion is permitted to be considered as a separate building for the purpose of determining building height, provided
(a)each separated portion is not more than 3 storeys in building height and is used only for residential occupancies other than a retirement home, and
(b)the unobstructed path of travel for a firefighter from the nearest street to one entrance of each separated portion is not more than 45 m.
(See Note A-1.3.3.4.(2))
(3)The vertical fire separation referred to in Sentence (2) may terminate at the floor assembly immediately above a basement provided the basement conforms to Article 3.2.1.2. of Division B.
Open OBC Div. A 1.3.3.4. in the code viewer
OBC Div. B 1.1.3.1. Climatic and Seismic Values
(1)The climatic and seismic values required for the design of buildings under this Code shall be in conformance with the climatic and seismic values provided in MMAH Supplementary Standard SB-1, "Climatic and Seismic Data".
(2)The outside winter design temperatures determined from MMAH Supplementary Standard SB-1, "Climatic and Seismic Data", shall be those listed for the January 2.5% values. (See Note A-1.1.3.1.(2))
Open OBC Div. B 1.1.3.1. in the code viewer
OBC Div. A 1.4.1.2.(1) Fixture
Fixture means a receptacle, appliance, apparatus or other device that discharges sewage or clear water waste, and includes a floor drain.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. A 1.4.1.2.(1) Sanitary unit
Sanitary unit means a water closet, urinal, bidet or bedpan washer.
Open OBC Div. A 1.4.1.2.(1) in the code viewer

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OBC Div. A 1.4.1.2.(1) Public use
Public use means, when applied to plumbing fixtures, fixtures in general washrooms of schools, gymnasiums, hotels, bars, public comfort stations and other installations in which fixtures are installed so that their use is unrestricted.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. A 1.4.1.2.(1) Private use
Private use means, when applied to plumbing fixtures, fixtures in residences and apartments, in private bathrooms of hotels, and in similar installations in other buildings for a single household or an individual.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. A 1.4.1.2.(1) Vertical service space
Vertical service space means a shaft oriented essentially vertically that is provided in a building to facilitate the installation of building services including mechanical, electrical and plumbing installations and facilities such as elevators, refuse chutes and linen chutes.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. A 2.2.1.1. Objectives
(1)The objectives of this Code are as follows: (See Note A-2.2.1.1.(1))
OS Safety
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in or adjacent to the building will be exposed to an unacceptable risk of injury.
OS1 Fire Safety
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in or adjacent to the building will be exposed to an unacceptable risk of injury due to fire. The risks of injury due to fire addressed in this Code are those caused by—
OS1.1 – fire or explosion occurring
OS1.2 – fire or explosion impacting areas beyond its point of origin
OS1.3 – collapse of physical elements due to a fire or explosion
OS1.4 – fire safety systems failing to function as expected
OS1.5 – persons being delayed in or impeded from moving to a safe place during a fire emergency
OS2 Structural Safety
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in or adjacent to the building will be exposed to an unacceptable risk of injury due to structural failure. The risks of injury due to structural failure addressed in this Code are those caused by—
OS2.1 – loads bearing on the building elements that exceed their loadbearing capacity
OS2.2 – loads bearing on the building that exceed the loadbearing properties of the supporting medium
OS2.3 – damage to or deterioration of building elements
OS2.4 – vibration or deflection of building elements
OS2.5 – instability of the building or part thereof
OS2.6 – collapse of the excavation
OS3 Safety in Use
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in or adjacent to the building will be exposed to an unacceptable risk of injury due to hazards. The risks of injury due to hazards addressed in this Code are those caused by—
OS3.1 – tripping, slipping, falling, contact, drowning or collision
OS3.2 – contact with hot surfaces or substances
OS3.3 – contact with energized equipment
OS3.4 – exposure to hazardous substances
OS3.5 – exposure to high levels of sound from fire alarm systems
OS3.6 – persons becoming trapped in confined spaces
OS3.7 – persons being delayed in or impeded from moving to a safe place during an emergency (See Note A-2.2.1.1.(1))
OS4 Resistance to Unwanted Entry
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be exposed to an unacceptable risk of injury due to the building's low level of resistance to unwanted entry. The risks of injury due to unwanted entry addressed in this Code are those caused by—
OS4.1 – intruders being able to force their way through locked doors or windows
OS4.2 – occupants being unable to identify potential intruders as such
OH Health
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person will be exposed to an unacceptable risk of illness.
OH1 Indoor Conditions
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be exposed to an unacceptable risk of illness due to indoor conditions. The risks of illness due to indoor conditions addressed in this Code are those caused by—
OH1.1 – inadequate indoor air quality
OH1.2 – inadequate thermal comfort
OH1.3 – contact with moisture
OH2 Sanitation
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be exposed to an unacceptable risk of illness due to unsanitary conditions. The risks of illness due to unsanitary conditions addressed in this Code are those caused by—
OH2.1 – exposure to human or domestic waste
OH2.2 – consumption of contaminated water
OH2.3 – inadequate facilities for personal hygiene
OH2.4 – contact with contaminated surfaces
OH2.5 – contact with vermin and insects
OH2.6 – unsanitary conditions caused by exposure to human or domestic waste
OH3 Noise Protection
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be exposed to an unacceptable risk of illness due to high levels of sound originating in adjacent spaces in the building. The risks of illness due to high levels of sound addressed in this Code are those caused by—
OH3.1 – exposure to airborne sound transmitted through assemblies separating dwelling units from adjacent spaces in the building.
OH4 Vibration and Deflection Limitation
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be exposed to an unacceptable risk of illness due to high levels of vibration or deflection of building elements.
OH5 Hazardous Substances Containment
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, the public will be exposed to an unacceptable risk of illness due to the release of hazardous substances from the building.
OH6 Privacy
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, a person in the building will be provided with an unacceptable level of privacy.
OH7 View to the Outdoors
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person in the building will be unable to experience a view to the outdoors.
OA Accessibility
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person with a physical or sensory limitation will be unacceptably impeded from accessing or using the building or its facilities.
OA1 Barrier-Free Path of Travel
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person with a physical or sensory limitation will be unacceptably impeded from accessing the building or circulating within it.
OA2 Barrier-Free Facilities
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, a person with a physical or sensory limitation will be unacceptably impeded from using the building's facilities.
OP Fire, Structural, Water and Sewage Protection of Buildings
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, the building or adjacent buildings will be exposed to an unacceptable risk of damage due to fire or structural insufficiency, or the building or part thereof will be exposed to an unacceptable risk of loss of use also due to structural insufficiency.
OP1 Fire Protection of the Building
An objective of this Code is to limit the probability that, as a result of its design or construction, the building will be exposed to an unacceptable risk of damage due to fire. The risks of damage due to fire addressed in this Code are those caused by—
OP1.1 – fire or explosion occurring
OP1.2 – fire or explosion impacting areas beyond its point of origin
OP1.3 – collapse of physical elements due to a fire or explosion
OP1.4 – fire safety systems failing to function as expected
OP2 Structural Sufficiency of the Building
An objective of this Code is to limit the probability that, as a result of its design or construction, the building or part thereof will be exposed to an unacceptable risk of damage or loss of use due to structural failure or lack of structural serviceability. The risks of damage and of loss of use due to structural failure or lack of structural serviceability addressed in this Code are those caused by—
OP2.1 – loads bearing on the building elements that exceed their loadbearing capacity
OP2.2 – loads bearing on the building that exceed the loadbearing properties of the supporting medium
OP2.3 – damage to or deterioration of building elements
OP2.4 – vibration or deflection of building elements
OP2.5 – instability of the building or part thereof
OP2.6 – instability or movement of the supporting medium
OP3 Protection of Adjacent Buildings from Fire
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, adjacent buildings will be exposed to an unacceptable risk of damage due to fire. The risks of damage to adjacent buildings due to fire addressed in this Code are those caused by—
OP3.1 – fire or explosion impacting areas beyond the building of origin
OP4 Protection of Adjacent Buildings from Structural Damage
An objective of this Code is to limit the probability that, as a result of the design or construction of the building, adjacent buildings will be exposed to an unacceptable risk of structural damage. The risks of structural damage to adjacent buildings addressed in this Code are those caused by—
OP4.1 – settlement of the medium supporting adjacent buildings
OP4.2 – collapse of the building or portion thereof onto adjacent buildings
OP4.3 – impact of the building on adjacent buildings
OP4.4 – collapse of the excavation
OP5 Water and Sewage Protection of Buildings and Facilities
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, a building will be exposed to unacceptable risk of damage due to leakage of service water or sewage.
OR Resource Conservation
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, a resource will be exposed to an unacceptable risk of depletion or the capacity of the infrastructure supporting the use, treatment or disposal of the resource will be exposed to an unacceptable risk of being exceeded.
OR1 Water and Energy Conservation
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, a resource will be exposed to an unacceptable risk of depletion. The risks of resource depletion addressed in this Code are those caused by—
OR1.1 – the consumption of water
OR1.2 – the consumption of energy
OR2 Infrastructure Capacity
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, the capacity of the infrastructure supporting the use, treatment or disposal of a resource will be exposed to an unacceptable risk of being exceeded. The risks of exceeding capacity addressed in this Code are those caused by—
OR2.1 – excessive demand on the infrastructure
OE Environmental Integrity
An objective of this Code is to limit the probability that, as a result of the design or construction or operation of the building, the natural environment will be exposed to an unacceptable risk of degradation.
OE1 Air Quality
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, the natural environment will be exposed to an unacceptable risk of degradation due to emissions of greenhouse gases into the air. The risks of degradation addressed in this Code are those caused by—
OE1.1 – emissions of greenhouse gases into the air
OE1.2 – the release of contaminants, other than greenhouse gases, into the air
OE2 Water and Soil Quality
An objective of this Code is to limit the probability that, as a result of the design or construction of a building, the natural environment will be exposed to an unacceptable risk of degradation due to excessive release of contaminants into water or soil.
OC Conservation of Buildings
An objective of this Code is to limit the probability that, as a result of the extension, material alteration or repair of an existing building or a change in use of an existing building, the existing building cannot be acceptably conserved.
Open OBC Div. A 2.2.1.1. in the code viewer
OBC Div. A 3.2.1.1. Functional Statements
(1)The objectives of this Code are achieved by measures, such as those described in the acceptable solutions in Division B, that are intended to allow the building or its elements to perform the following functions: (See Note A-3.2.1.1.(1))
F01 To minimize the risk of accidental ignition.
F02 To limit the severity and effects of fire or explosions.
F03 To retard the effects of fire on areas beyond its point of origin.
F04 To retard failure or collapse due to the effects of fire.
F05 To retard the effects of fire on emergency egress facilities.
F06 To retard the effects of fire on facilities for notification, suppression and emergency response.
F10 To facilitate the timely movement of persons to a safe place in an emergency.
F11 To notify persons, in a timely manner, of the need to take action in an emergency.
F12 To facilitate emergency response.
F13 To notify emergency responders, in a timely manner, of the need to take action in an emergency.
F20 To support and withstand expected loads and forces.
F21 To limit or accommodate dimensional change.
F22 To limit movement under expected loads and forces.
F23 To maintain equipment in place during structural movement.
F30 To minimize the risk of injury to persons as a result of tripping, slipping, falling, contact, drowning or collision.
F31 To minimize the risk of injury to persons as a result of contact with hot surfaces or substances.
F32 To minimize the risk of injury to persons as a result of contact with energized equipment.
F33 To limit the level of sound of a fire alarm system.
F34 To resist or discourage unwanted access or entry.
F35 To facilitate the identification of potential intruders.
F36 To minimize the risk that persons will be trapped in confined spaces.
F40 To limit the level of contaminants.
F41 To minimize the risk of generation of contaminants.
F42 To resist the entry of vermin and insects.
F43 To minimize the risk of release of hazardous substances.
F44 To limit the spread of hazardous substances beyond their point of release.
F45 To minimize the risk of the spread of diseases through communal shower facilities.
F46 To minimize the risk of contamination of potable water.
F50 To provide air suitable for breathing.
F51 To maintain appropriate air and surface temperatures.
F52 To maintain appropriate relative humidity.
F53 To maintain appropriate indoor/outdoor air pressure differences.
F54 To limit drafts.
F55 To resist the transfer of air through environmental separators.
F56 To limit the transmission of airborne sound into a dwelling unit from spaces elsewhere in the building.
F60 To control the accumulation and pressure of water on and in the ground.
F61 To resist the ingress of precipitation, water or moisture from the exterior or from the ground.
F62 To facilitate the dissipation of water and moisture from the building.
F63 To limit moisture condensation.
F70 To provide potable water.
F71 To provide facilities for personal hygiene.
F72 To provide facilities for the sanitary disposal of human and domestic wastes.
F73 To facilitate access to and circulation in the building and its facilities by persons with physical or sensory limitations.
F74 To facilitate the use of the building's facilities by persons with physical or sensory limitations.
F80 To resist deterioration resulting from expected service conditions.
F81 To minimize the risk of malfunction, interference, damage, tampering, lack of use or misuse.
F82 To minimize the risk of inadequate performance due to improper maintenance or lack of maintenance.
F101 To limit unwanted visual exposure.
F102 To provide a view to the outdoors in buildings.
F110 To control the release of contaminants into soil, groundwater, surface water, and air.
F111 To minimize the risk of malfunction, damage or failure of a sewage system.
F112 To provide adequate treatment of sanitary sewage and effluent.
F113 To minimize the risk of injury as a result of contact with sanitary sewage or partially treated effluent.
F120 To minimize the risk of injury to persons entering or exiting the pool, as a result of unfamiliarity with the pool.
F121 To minimize the risk of injury to persons using the pool, as a result of unfamiliarity with the pool.
F122 To minimize the risk of contamination of pool water.
F123 To facilitate timely response to incapacitated pool users.
F124 To minimize the risk of entrapment or injury to a person within the pool, as a result of water, air or vacuum action.
F130 To limit excessive water consumption.
F131 To limit excessive energy consumption.
F132 To limit excessive demand on the infrastructure.
F133 To limit excessive peak demand on the infrastructure.
F140 To facilitate the reuse and material alteration and repair of existing buildings.
F150 To limit excessive emissions of greenhouse gases into the air.
F151 To limit the excessive release of contaminants, other than greenhouse gases, into the air.
Open OBC Div. A 3.2.1.1. in the code viewer
OBC Div. B 3.1.5.19. Combustible Piping Materials
(1)Except as permitted by Clause 3.1.5.2.(1)(d) and Article 3.1.5.25. and Sentences (2) and (3), combustible piping and tubing and associated adhesives are permitted to be used in a building required to be of noncombustible construction provided that, except when concealed in a wall or concrete floor slab, they
(a)have a flame-spread rating not more than 25, and
(b)if used in a building described in Subsection 3.2.6., have a smoke developed classification not more than 50.
(2)Combustible sprinkler piping is permitted to be used within a sprinklered floor area in a building required to be of noncombustible construction. (See also Article 3.2.5.13.)
(3)Polypropylene pipes and fittings are permitted to be used for drain, waste and vent piping for the conveyance of highly corrosive materials and for piping used to distribute distilled or dialyzed water in laboratory and hospital facilities in a building required to be of noncombustible construction, provided
(a)the building is sprinklered throughout,
(b)the piping is not located in a vertical shaft, and
(c)piping that penetrates a fire separation is sealed at the penetration by a firestop that has an FT rating not less than the fire-resistance rating of the fire separation when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," with a pressure differential of 50 Pa between the exposed and unexposed sides, with the higher pressure on the exposed side.
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OBC Div. B 3.1.5.20. Combustible Plumbing Fixtures
(1)Combustible plumbing fixtures including wall and ceiling enclosures that form part of the plumbing fixture, are permitted in a building required to be of noncombustible construction provided they are constructed of material having a flame-spread rating and smoke developed classification not more than that permitted for the wall surface of the room or space in which they are installed.
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OBC Div. B 3.1.5.26. Combustible Components in Public Pools and Public Spas
(1)Combustible fittings and components in a public pool or public spa, including main drains, piping, skimmers, return inlets, steps, ladder rungs and liners, are permitted in a building required to be of noncombustible construction.
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OBC Div. B 3.1.13.3. Bathrooms in Residential Suites
(1)The flame-spread rating of interior wall and ceiling finishes for a bathroom within a suite of residential occupancy shall be not more than 200.
(2)Plumbing fixtures shall have a flame-spread rating not more than 200.
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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.
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OBC Div. B 3.1.9.1. Firestops
(1)Except as provided in Sentences (2) to (7) and Article 3.1.9.3., penetrations of a fire separation or a membrane forming part of an assembly required to have a fire-resistance rating shall be
(a)sealed by a firestop that, when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," has an F rating not less than the required fire-resistance rating of the fire separation, or
(b)cast-in-place, where the item penetrating the fire separation is steel, ferrous, copper, concrete or masonry. (See Note A-3.1.9.1.(1)(b))
(See also Article 3.1.9.4. for requirements regarding penetrations by combustible drain, waste and vent piping.)
(2)Except as permitted in Sentence (6), penetrations of a firewall or a horizontal fire separation that is required to have a fire-resistance rating in conformance with Article 3.2.1.2. shall be sealed at the penetration by a firestop that, when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," has an FT rating not less than the fire-resistance rating for the fire separation.
(3)Except as permitted in Sentences (6) and (7), penetrations of a fire separation in conformance with Sentence 3.6.4.2.(2) shall be sealed by a firestop that, when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," has an FT rating not less than the fire-resistance rating for the fire separation of the assembly.
(4)Sprinklers are permitted to penetrate a fire separation or a membrane forming part of an assembly required to have a fire-resistance rating without having to meet the firestop requirements of Sentences (1) to (3), provided the annular space created by the penetration of a fire sprinkler is covered by a metal escutcheon plate in accordance with NFPA 13, "Standard for the Installation of Sprinkler Systems."
(5)Unless specifically designed with a firestop, fire dampers are permitted to penetrate a fire separation or a membrane forming part of an assembly required to have a fire-resistance rating without having to meet the firestop requirements of Sentences (1) to (3), provided the fire damper is installed in conformance with NFPA 80, "Standard for Fire Doors and Other Opening Protectives."
(6)Service equipment penetrations through a horizontal fire separation having a fire-resistance rating as described in Sentences (2) and (3) that are contained within the cavity of a wall above and below the horizontal fire separation are permitted to be sealed at the penetration by a firestop that, when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," has an F rating not less than the fire-resistance rating for the fire separation.
(7)Service equipment penetrations through a horizontal fire separation having a fire-resistance rating as described in Sentence (3) are permitted to be sealed at the penetration by a firestop that, when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," has an F rating not less than the fire-resistance rating for the fire separation, provided the penetration
(a)is contained within the concealed space of a floor or ceiling assembly having a fire-resistance rating,
(b)is located above a ceiling membrane that is a horizontal fire separation, or
(c)is contained within a horizontal service space conforming to Subsection 3.6.4. that is directly above or below the floor.
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OBC Div. B 3.1.9.2. Service Equipment Penetrations
(1)Ducts, electrical outlet boxes, pipes, totally enclosed raceways, optical fibre cables, electrical wires and cables, and other similar service equipment are permitted to penetrate a fire separation or a membrane forming part of an assembly required to have a fire-resistance rating, provided they are protected at the penetration with a firestop conforming to Sentence 3.1.9.1.(1). (See Note A-3.1.9.2.(1))
(2)Combustible totally enclosed raceways that are embedded in a concrete floor slab are permitted in an assembly required to have a fire-resistance rating, provided the concrete cover between the raceway and the bottom of the slab is not less than 50 mm.
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OBC Div. B 3.1.9.4. Combustible Piping Penetrations
(1)Combustible sprinkler piping is permitted to penetrate a fire separation provided the fire compartments on each side of the fire separation are sprinklered.
(2)Combustible water distribution piping is permitted to penetrate a fire separation that is required to have a fire-resistance rating, provided the piping is protected at the penetration with a firestop in conformance with Clause (4)(a) or (b).
(3)Except as permitted by Sentences (4), (5), (7) and (8), combustible piping shall not be used in a drain, waste and vent piping system if any part of that system penetrates
(a)a fire separation required to have a fire-resistance rating, or
(b)a membrane that forms part of an assembly required to have a fire-resistance rating.
(4)Combustible drain, waste and vent piping is permitted to penetrate a fire separation required to have a fire-resistance rating or a membrane that forms part of an assembly required to have a fire-resistance rating, provided
(a)except as provided in Clause (b), the piping is sealed at the penetration by a firestop that has an F rating not less than the fire-resistance rating required for the fire separation when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems,"
(b)in buildings more than 3 storeys in building height, the piping is sealed at the penetration by a firestop that has an F rating not less than the fire-resistance rating required for the fire separation when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," with a pressure differential of 50 Pa between the exposed and unexposed sides, with the higher pressure on the exposed side, and
(c)the piping is not located in a vertical service space.
(5)Combustible drain, waste and vent piping is permitted on one side of a vertical fire separation provided it is not located in a vertical service space.
(6)Combustible piping for central vacuum systems is permitted to penetrate a fire separation, provided the installation conforms to the requirements that apply to combustible drain, waste and vent piping specified in Sentence (4).
(7)Except as provided in Sentence (8), penetrations of a fire separation that incorporate transitions between combustible and noncombustible drain, waste and vent piping shall be sealed by a firestop that has an F rating not less than the fire-resistance rating required for the fire separation when subjected to the fire test method in CAN/ULC-S115, "Standard Method of Fire Tests of Firestop Systems," with a pressure differential of 50 Pa between the exposed and unexposed sides, with the higher pressure on the exposed side.
(8)Transitions between vertical noncombustible drain, waste and vent piping and combustible branches for drain, waste and vent piping are permitted on either side of a fire separation, provided they are not located in a vertical service space. (See Note A-3.1.9.4.(8))
(9)Combustible piping not more than 25 mm in diameter containing chlorine gas is permitted to penetrate a fire separation between a chlorine gas service room built in conjunction with a public pool or public spa and the remainder of the building, provided the piping is sealed at the penetration by a firestop in conformance with Clause 3.1.9.1.(1)(a).
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OBC Div. B 3.1.11.2. Fire Blocks in Wall Assemblies
(1)Except as permitted by Sentence (2), fire blocks conforming to Article 3.1.11.7. shall be provided to block off concealed spaces within a wall assembly
(a)at every floor level,
(b)at every ceiling level where the ceiling forms part of an assembly required to have a fire-resistance rating, and
(c)so that the maximum horizontal dimension is not more than 20 m and the maximum vertical dimension is not more than 3 m.
(2)Fire blocks conforming to Sentence (1) are not required provided
(a)the wall space is filled with insulation,
(b)the exposed construction materials and any insulation within the wall space are noncombustible,
(c)the exposed materials within the wall space, including insulation but not including wiring, piping or similar services, have a flame-spread rating not more than 25 on any exposed surface, or on any surface that would be exposed by cutting through the material in any direction, and fire blocks are installed so that the vertical distance between them is not more than 10 m, or
(d)the insulated wall assembly contains not more than one concealed air space, and the horizontal thickness of that air space is not more than 25 mm.
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OBC Div. B 3.1.11.7. Fire Block Materials
(1)Except as permitted by Sentences (2) to (5) and (8), fire blocks shall remain in place and prevent the passage of flames for not less than 15 min when subjected to the standard fire exposure in CAN/ULC-S101, "Standard Method of Fire Endurance Tests of Building Construction and Materials."
(2)Gypsum board not less than 12.7 mm thick and sheet steel not less than 0.38 mm thick need not be tested in conformance with Sentence (1) provided all joints have continuous support.
(3)In a building required to be of noncombustible construction, wood nailing elements described in Article 3.1.5.8. need not be tested in conformance with Sentence (1).
(4)In a building or part of a building permitted to be of encapsulated mass timber construction, wood nailing elements referred to in Article 3.1.6.11. need not be tested in conformance with Sentence (1).
(5)In a building permitted to be of combustible construction, in a combustible roof system permitted by Sentences 3.1.5.3.(2) and 3.1.6.7.(1), and in a raised platform permitted by Sentence 3.1.5.10.(2) or 3.1.6.12.(1), fire blocks are permitted to be
(a)solid lumber or a structural composite lumber product conforming to ASTM D5456, "Standard Specification for Evaluation of Structural Composite Lumber Products," not less than 38 mm thick,
(b)phenolic bonded plywood, OSB, waferboard or oriented strandboard not less than 12.5 mm thick with joints supported, or
(c)two thicknesses of lumber or a structural composite lumber product conforming to ASTM D5456, "Standard Specification for Evaluation of Structural Composite Lumber Products," each not less than 19 mm thick with joints staggered, where the width or height of the concealed space requires more than one piece of lumber or structural composite lumber product not less than 38 mm thick to block off the space.
(6)Openings through materials referred to Sentences (1) to (5) shall be protected to maintain the integrity of the construction.
(7)Where materials referred to Sentences (1) to (5) are penetrated by construction elements or by service equipment, a firestop shall be used to seal the penetration. (See Note A-3.1.11.7.(7))
(8)In buildings permitted to be of combustible construction, semi-rigid fibre insulation board produced from glass, rock or slag is permitted to be used to block the vertical space in a double stud wall assembly formed at the intersection of the floor assembly and the walls, provided the width of the vertical space does not exceed 25 mm and the insulation board
(a)has a density not less than 45 kg/m²,
(b)is securely fastened to one set of studs,
(c)extends from below the bottom of the top plates in the lower storey to above the top of the bottom plate in the upper storey, and
(d)completely fills the portion of the vertical space between the headers and between the wall plates. (See Note A-3.1.11.7.(8))
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OBC Div. B 3.6.4.3. Plenum Requirements
(1)A concealed space used as a plenum within a floor assembly or within a roof assembly need not conform to Sentence 3.1.5.18.(1) and Article 3.6.5.1. provided
(a)all materials within the concealed space have a flame-spread rating not more than 25 and a smoke developed classification not more than 50, except for
(i)tubing for pneumatic controls,
(ii)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 conform to Sentences 3.1.4.3.(2) and 3.1.5.21.(2),
(iii)totally enclosed non-metallic raceways with an FT6 rating, when tested in accordance with Clause 3.1.5.23.(1)(a), in buildings required to be of noncombustible construction or in buildings or parts of buildings permitted to be of encapsulated mass timber construction, and
(iv)totally enclosed non-metallic raceways with an FT4 rating, when tested in accordance with Clause 3.1.5.23.(1)(a), in buildings permitted to be of combustible construction, and,
(b)the supports for the ceiling membrane are of noncombustible material having a melting point not below 760°C.
(2)If a concealed space referred to in Sentence (1) is used as a return-air plenum and incorporates a ceiling membrane that forms part of the required fire-resistance rating of the assembly, every opening through the membrane shall be protected by a fire stop flap that
(a)stops the flow of air into the concealed space in the event of a fire,
(b)is supported in a manner that will maintain the integrity of the ceiling membrane for the duration of time required to provide the required fire-resistance rating,
(c)conforms to CAN/ULC-S112.2, "Standard Method Fire Test of Ceiling Firestop Flap Assemblies," and
(d)activates at a temperature approximately 30°C above the normal maximum temperature that occurs in the return-air plenum, whether the air duct system is operating or shut down.
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OBC Div. B 3.4.4.4. Integrity of Exits
(1)A fire separation that separates an exit from the remainder of the building shall have no openings except for
(a)standpipe and sprinkler piping,
(b)electrical wires and cables, totally enclosed noncombustible raceways and noncombustible piping that serve only the exit,
(c)openings required by the provisions of Subsection 3.2.6.,
(d)exit doorways,
(e)wired glass and glass block permitted by Article 3.1.8.16., and
(f)a sprinkler protected glazed wall assembly conforming to Article 3.1.8.20.
(2)Exits within scissors stairs and other contiguous exit stairways shall be separated from each other by a smoke-tight fire separation having a fire-resistance rating not less than that required for the floor assembly through which they pass.
(3)Fire separations separating contiguous stairs described in Sentence (2) shall not be pierced by doorways, ductwork, piping or any other openings that affect the continuity of the separation.
(4)A fuel-fired appliance shall not be installed in an exit.
(5)An exit shall not be used as a plenum for a heating, ventilating or air-conditioning system.
(6)An exit shall be designed for no purpose other than for exiting, except that an exit is permitted also to be designed to serve as an access to a floor area.
(7)A service room shall not open directly into an exit.
(8)Storage rooms, washrooms, toilet rooms, laundry rooms and similar ancillary rooms shall not open directly into an exit.
(9)Service spaces referred to in Sentence 3.2.1.1.(8) shall not open directly into an exit.
(10)In elementary and secondary schools, an exit shall be designed so that it does not serve as an access from one portion of a floor area to another portion of the same floor area.
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OBC Div. B 3.6.3.1. Fire Separations for Vertical Service Spaces
(1)Except as provided in Articles 3.6.3.3. and 3.6.3.5. and Section 3.5., a vertical service space shall be separated from all other portions of each adjacent storey by a fire separation having a fire-resistance rating conforming to Table 3.6.3.1. for the fire-resistance rating required by Subsection 3.2.2. for
(a)the floor assembly above the storey, or
(b)the floor assembly below the storey, if there is no floor assembly above. (See Note A-3.6.3.1.(1))
(2)A vertical service space that does not extend through the roof of a building shall be enclosed at the top with construction having a fire-resistance rating not less than that required for the vertical service space walls.
(3)A vertical service space that does not extend to the bottom of a building shall be enclosed at the lowest level with construction having a fire-resistance rating not less than that required for the vertical service space walls.
(4)A vent from a vertical service space not extending to the roof shall be enclosed within the building with construction having a fire-resistance rating not less than that required for the vertical service space walls.
(5)Only openings that are necessary for the use of the vertical service space shall be permitted through a vertical service space enclosure.
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OBC Div. B 3.6.3.3. Linen and Refuse Chutes
(1)A linen chute or refuse chute shall
(a)be impervious to moisture,
(b)have a smooth internal surface,
(c)be corrosion-resistant,
(d)be constructed of noncombustible material, and
(e)be located in a shaft in which there are no services other than noncombustible drain, waste and vent piping or noncombustible water piping.
(2)A shaft containing a linen chute or refuse chute shall have a fire-resistance rating conforming to Sentence 3.6.3.1.(1), but not less than
(a)1 h if the chute outlet for the discharge room is protected by an automatic, self-latching closure held open by a fusible link, or
(b)2 h if no closure is provided at the chute outlet into the discharge room.
(3)An interior linen chute or refuse chute shall extend not less than 1 m above the roof and shall be vented above the roof with a vent which
(a)has an unobstructed area not less than the cross-sectional area of the chute, and
(b)is equipped with a cover that will open automatically, or that can be opened manually, in the event of a fire in the
(4)Intake openings for a linen chute or a refuse chute shall
(a)have an area not more than 60% of the cross-sectional area of the chute, and
(b)be fitted with closures designed to close automatically and latch after use.
(5)Intake openings for a linen chute or a refuse chute shall be located in rooms or compartments that
(a)have no dimension less than 750 mm,
(b)are separated from the remainder of the building by a fire separation with a fire-resistance rating not less than 45 min,
(c)are designed for no other purpose, and
(d)do not open directly into an exit.
(6)Sprinklers shall be installed at the top of each linen chute or refuse chute, at alternate floor levels and in the room or bin into which the chute discharges.
(7)The room into which a linen chute discharges shall be separated from the remainder of the building by a fire separation with a fire-resistance rating not less than 1 h.
(8)A refuse chute shall be equipped at the top with spray equipment for washing-down purposes.
(9)A refuse chute shall discharge only into a room or bin separated from the remainder of the building by a fire separation with a fire-resistance rating not less than 2 h.
(10)The room or bin into which a refuse chute discharges shall be of sufficient size to contain the refuse between normal intervals of emptying, be impervious to moisture and be equipped with a water connection and floor drain for washing-down purposes.
(11)A room into which a refuse chute discharges shall contain no service equipment that is not related to refuse handling and disposal.
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