Special buildings and existing buildings (Detection, Lighting and Power)

Last updated October 22, 2026

Values this chapter turns on

generator run time for an air-supported blower: 4 h; generator run time for an air-supported blower
min gap between portable groups, no alarm extension: 12 m; min gap between portable groups, no alarm extension
natural light, as share of self-storage corridor area: 4%; natural light, as share of self-storage corridor area
max travel to a transit station reporting device: 90 m; max travel to a transit station reporting device

Sections 3.9. to 3.18. adjust the general Part 3 rules for particular building types. For this exam, focus on the alarm, lighting, emergency power and electrical items in each. These Sections are short, so an open-book candidate who knows which Section to open can answer most questions in under a minute.

Portable classrooms and self-storage buildings

Portable classrooms. The main school's fire alarm system must be extended to the portables, with a separate zone indicator on the annunciator OBC Div. B 3.9.3.3.. The extension is not needed in two cases:

the portables are 6 m or more apart (Sentence (3)); or
there are not more than 12 portables on the site, and either they are less than 6 m apart with Subsection 3.2.3. applied between them, or they are grouped. In a group, portables are less than 6 m apart, there are not more than six per group, the facing walls are rated 45 min from inside the classroom, and the groups are 12 m or more apart.

Self-service storage buildings are buildings that provide individual storage spaces to the public and are open to the public only for that purpose (Div. A). Section 3.10. splits them by size:

Item	Multi-storey (or with basement or mezzanine), 3.10.3.	1 storey, no basement or mezzanine, 3.10.4.
Fire alarm	Required; manual stations in the first storey only in corridors	Subsection 3.2.4. does not apply
Smoke alarms in a dwelling unit	Under 3.2.4.	Article 3.2.4.20. still applies
Fire access routes	At least 9 m wide	At least 9 m wide

See OBC Div. B 3.10.3.3., 3.10.4.4. and 3.10.3.4.. Corridors need natural light equal to at least 4% of the corridor area, uniformly distributed. Otherwise they need emergency lighting averaging at least 10 lx, powered as 3.2.7.4. requires OBC Div. B 3.10.2.4..

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Pools and spas

For public pools, OBC Div. B 3.11.10.1. sets these levels:

Pool item	Value
Dressing, locker, shower rooms, washrooms, passageways	At least 200 lx at floor level
Indoor pool deck and water surface	At least 200 lx
Outdoor pool used after sundown	At least 100 lx
Independent emergency lighting (deck, washrooms, showers, lockers, water surface, egress)	At least 10 lx

The emergency lighting system must switch on automatically when normal pool lighting power fails. It applies to every indoor pool and to outdoor pools used after sundown. Its power supply follows 3.2.7.4.(1), 3.2.7.5. and 3.2.7.7.(1). Class A pools need an emergency telephone beside the deck; Class B pools need one within 30 m. Recirculating pumps need a labelled emergency stop button that also triggers an audible and visual signal.

Public spas follow the pool lighting rules. They need an emergency telephone within 30 m and a pump emergency stop within 15 m, in sight of the users and separate from the timer. Where a spa and pool share a room, either stop button shuts down all the pumps OBC Div. B 3.12.5.1..

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Rapid transit stations

A rapid transit station is a building or part used to load and unload passengers of a rapid transit system. Open air shelters at street level are excluded OBC Div. B 3.13.1.2.. Emergency lighting in public areas averages at least 10 lx, on emergency power for 30 min OBC Div. B 3.13.3.7..

The fire alarm follows 3.2.4., with these changes in Subsection 3.13.5.:

manual stations and audible signal appliances need not be installed;
fire detectors are needed in every service room, ancillary space, leased space, booth and kiosk, unless the area is sprinklered;
a central supervising station conforming to CAN/ULC-S561 monitors the station;
the annunciator must be readily accessible to firefighters, in or within view of a designated collector's booth;
emergency power follows 3.2.7.8.;
a public address system and a two-way telephone system are required, with phones at the collector's booth and at each end of each platform;
emergency reporting devices must be within 90 m of travel from any point in the public area.

Every station also needs an emergency ventilation system conforming to NFPA 130 OBC Div. B 3.13.7.1.. The exam can ask which standard, not its content.

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Tents and air-supported structures

In tents and air-supported structures, the electrical system and equipment, including fuses and switches, must be inaccessible to the public. Cables on the ground in public areas go in trenches or under protective covers OBC Div. B 3.14.1.10., 3.14.2.7.. An air-supported structure for an assembly occupancy of more than 200 persons needs one of two backups: an automatic engine-generator able to run one blower continuously for 4 h, or a supplementary blower driven by an automatic internal combustion engine OBC Div. B 3.14.2.6..

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Rack storage and existing buildings

Shelf and rack storage systems. These are self-contained structural systems with elevated platforms or walkways for personnel (Div. A). They need:

normal lighting averaging 50 lx on walkways and platforms;
emergency lighting at the 3.2.7.3.(2) and (3) levels (10 lx average, 1 lx minimum), for the 3.2.7.4. durations OBC Div. B 3.16.1.5.;
sprinklers in the floor area, including under all platforms and walkways OBC Div. B 3.16.1.6.;
noncombustible draft stops at least 450 mm deep at stair openings, unless the platforms are of open construction;
electrical supervision of the sprinklers to the annunciator, or to the person controlling the building where there is no fire alarm system;
fire department notification of waterflow.

Existing buildings. Section 3.18. applies when a change of use is proposed OBC Div. B 3.18.1.1.. The triggers include:

a change of major occupancy marked "Y" in Division C Table 1.3.1.4.;
one Group C suite converted into several;
a farm building changed to a major occupancy;
a change to a post-disaster building or a retirement home;
an unknown previous occupancy;
a combustible building extended to more than four storeys.

For the occupancy changes in Subclauses (a)(i) to (iv) and (vi), the building must then meet Subsection 3.2.6. and Sections 3.7., 3.11. and 3.12. for the new occupancy OBC Div. B 3.18.2.1.. In every case its performance level must not drop, or compensating construction is needed OBC Div. B 3.18.2.2..

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Common traps

Assuming self-storage buildings never need a fire alarm. Multi-storey ones always do; only the 1-storey type without a basement or mezzanine is exempt.
Applying the 12-portable rule alone. The group conditions, including 12 m between groups, must all be met.
Giving rapid transit stations manual stations and horns. Both are expressly optional.
Using 2 h for the air-supported structure blower. It is 4 h.
Mixing up the spa distances: the phone is within 30 m, the stop button within 15 m.

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
Portable classrooms and self-storage buildings	A site has 10 portables in two groups of five, with the units in each group 4 m apart and facing walls rated 45 min. Subsection 3.2.3. is not applied between them.
Pools and spas	The emergency lighting system must switch on automatically when normal pool lighting power fails.
Rapid transit stations	A rapid transit station is a building or part used to load and unload passengers of a rapid transit system.
Tents and air-supported structures	In tents and air-supported structures, the electrical system and equipment, including fuses and switches, must be inaccessible to the public.
Rack storage and existing buildings	Shelf and rack storage systems.

Portable classrooms and self-storage buildings
A site has 10 portables in two groups of five, with the units in each group 4 m apart and facing walls rated 45 min. Subsection 3.2.3. is not applied between them.
Pools and spas
The emergency lighting system must switch on automatically when normal pool lighting power fails.
Rapid transit stations
A rapid transit station is a building or part used to load and unload passengers of a rapid transit system.
Tents and air-supported structures
In tents and air-supported structures, the electrical system and equipment, including fuses and switches, must be inaccessible to the public.
Rack storage and existing buildings
Shelf and rack storage systems.

Usual exam traps

Assuming self-storage buildings never need a fire alarm. Multi-storey ones always do; only the 1-storey type without a basement or mezzanine is exempt.
Applying the 12-portable rule alone. The group conditions, including 12 m between groups, must all be met.
Giving rapid transit stations manual stations and horns. Both are expressly optional.
Using 2 h for the air-supported structure blower. It is 4 h.
Mixing up the spa distances: the phone is within 30 m, the stop button within 15 m.

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Questions on Special buildings and existing buildings, 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 3.9.3.3. Fire Alarm Systems
(1)Except as provided in Sentences (2) and (3), the fire alarm system in the main school building shall be extended to the portable classrooms with a separate zone indicator on the annunciator.
(2)The requirements in Sentence (1) need not be provided where there are not more than 12 portables on a site and where
(a)the distance between portable classrooms is less than 6 m and the requirements of Subsection 3.2.3. are applied between the classrooms, or
(b)the portable classrooms are in groups where
(i)the distance between the classrooms is less than 6 m,
(ii)the number of classrooms in a group does not exceed six,
(iii)within a group of classrooms, the facing walls have a fire-resistance rating of 45 min, rated from inside the classroom, and
(iv)the distance between groups of classrooms is 12 m or more.
(3)The requirements in Sentence (1) need not be provided where the distance between portable classrooms is 6 m or more.
Open OBC Div. B 3.9.3.3. in the code viewer
OBC Div. A 1.4.1.2.(1) Self-service storage building
Self-service storage building means a building that is used to provide individual storage spaces to the public and that is open to the public only for those purposes.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. B 3.10.3.3. Fire Alarm Systems
(1)Except as provided in Sentences (2) and (3), the requirements in Subsection 3.2.4. shall apply.
(2)A fire alarm system shall be installed.
(3)Within the first storey, manual stations are required only in corridors.
Open OBC Div. B 3.10.3.3. in the code viewer
OBC Div. B 3.10.4.4. Fire Alarm Systems
(1)Except as provided in Sentence (2), the requirements in Subsection 3.2.4. shall not apply.
(2)The requirements for smoke alarms in Article 3.2.4.20. shall apply to a dwelling unit.
Open OBC Div. B 3.10.4.4. in the code viewer
OBC Div. B 3.10.3.4. Provisions for Firefighting
(1)Except as provided in Sentences (2) and (3), the requirements in Subsection 3.2.5. shall apply.
(2)Access routes for fire department vehicles shall be provided and shall be not less than 9 m wide.
(3)Hydrants shall be located in the access routes required in Sentence (2) so that
(a)for a building provided with a fire department connection for a standpipe system or a sprinkler system,
(i)a fire department pumper vehicle can be located adjacent to a hydrant, and
(ii)the unobstructed path of travel for the firefighter from the vehicle to the fire department connection is not more than 45 m, and
(b)for a building that is not sprinklered throughout, a fire department pumper vehicle can be located in the access route so that the unobstructed path of travel for the firefighter is not more than
(i)45 m from the hydrant to the vehicle, and
(ii)45 m from the vehicle to every opening in the building.
Open OBC Div. B 3.10.3.4. in the code viewer
OBC Div. B 3.10.2.4. Safety Requirements Within Floor Areas
(1)Except as provided in Sentences (2) to (12), the requirements in Section 3.3. shall apply.
(2)A corridor need not be constructed as a public corridor where the travel distance, measured from inside the rental space to the nearest exit, is not more than 15 m provided that the corridor walls
(a)are of noncombustible construction,
(b)have no openings other than doors and the doors are of solid construction, and
(c)are continuous from the floor to the underside of the floor above, the ceiling or the roof.
(3)Where the building is sprinklered throughout, doors in a public corridor do not require to be equipped with self-closing devices and latches provided that the travel distance is measured from inside the rental space to the nearest exit.
(4)Egress doors from a rental space are not required to swing in the direction of exit travel or swing on a vertical axis provided
(a)the area of the rental space is not more than 50 m² , and
(b)the distance of travel within the rental space is not more than 10 m.
(5)Where egress doors from a rental space open onto a corridor and swing in the direction of exit travel, the corridor shall be not less than 1,500 mm wide, and the doors shall be not more than 914 mm wide.
(6)Where egress doors from a rental space open onto a corridor and do not swing in the direction of exit travel, the corridor shall be not less than 1,100 mm in width.
(7)Dead-end corridors are not permitted.
(8)Corridors shall be provided with
(a)natural lighting that shall be uniformly distributed and be at least 4% of the corridor area, or
(b)emergency lighting, conforming to Sentences 3.2.7.4.(1) and (2), that shall provide average levels of illumination not less than 10 lx at floor level.
(9)Not more than two dwelling units shall be contained within one of the buildings on the property.
(10)Except as provided in Sentence (11), dwelling units shall be separated from the remainder of the building by a fire separation having a fire-resistance rating not less than 2 h.
(11)A fire separation is not required between a dwelling unit and an office where the office is not more than 50 m² in area.
(12)The fire separations required in Sentence 3.3.1.1.(1) need not be provided between individual rental spaces.
Open OBC Div. B 3.10.2.4. in the code viewer
OBC Div. B 3.11.10.1. Lighting and Emergency Provisions
(1)Except as provided in Sentences (2) and (3), rooms and spaces used by the public in conjunction with a public pool shall be capable of illumination to levels in compliance with Subsection 3.2.7.
(2)Dressing rooms, locker rooms, shower rooms, washrooms and passageways shall have an illumination level of at least 200 lx at floor level.
(3)An indoor pool or an outdoor pool that is intended to be open for use after sundown shall be equipped with a lighting system
(a)that will maintain at any point on the pool deck and on the pool water surface an illumination level of at least
(i)200 lx in the case of an indoor pool, and
(ii)100 lx in the case of an outdoor pool, and
(b)that makes the underwater areas of the pool clearly visible from any point on the pool deck.
(4)An outdoor pool that is intended to be open for use after sundown and an indoor pool shall be equipped with an independent emergency lighting system that automatically operates whenever the normal electrical power supply to a public pool lighting system fails.
(5)The independent emergency lighting system required in Sentence (4) shall be capable of illuminating the pool deck, washroom, shower, locker areas, pool water surface and all means of egress to a level of at least 10 lx.
(6)An emergency power supply for the emergency lighting system required in Sentence (4) shall comply with Sentences 3.2.7.4.(1) and 3.2.7.7.(1) and Article 3.2.7.5.
(7)An emergency telephone directly connected to an emergency service or to the local telephone utility shall be installed adjacent to the pool deck of every Class A pool.
(8)A telephone accessible for emergency use shall be installed for every Class B pool within 30 m of the pool.
(9)Every wave action pool shall have a public address system that shall be clearly audible in all portions of the pool.
(10)Every wave action pool shall have a communication system for the use of persons engaged in supervision or operation of the pool that shall be interconnected with each lifeguard control station, the first-aid room and the bather admission control centre.
(11)The public address system and the communication system described in Sentences (9) and (10) shall be interconnected.
(12)All recirculating pumps used in a public pool shall be capable of being deactivated by an emergency stop button clearly labelled and located at
(a)a Class A pool beside the telephone that is required in Sentence (7), and
(b)a Class B pool on the deck area.
(13)The emergency stop button in Sentence (12) shall, when used, activate an audible and a visual signal located by the emergency stop.
(14)An emergency sign containing the words in the event of an emergency push emergency stop button and use emergency phone, audible and visual signal will activate shall be in letters at least 25 mm high with a 5 mm stroke and posted above the emergency stop button.
Open OBC Div. B 3.11.10.1. in the code viewer
OBC Div. B 3.12.5.1. Lighting and Emergency Provisions
(1)In addition to the requirements of this Subsection, public spas shall comply with the requirements of Sentences 3.11.10.1.(1) to (6).
(2)An emergency telephone directly connected to an emergency service or to the local telephone utility shall be installed within 30 m of the public spa.
(3)All pumps used in a public spa shall be capable of being deactivated by an emergency stop button that is
(a)clearly labelled, and
(b)located at a point that is
(i)readily accessible to and within sight of persons using the public spa, and
(ii)within 15 m of the public spa.
(4)The emergency stop button required in Sentence (3) shall
(a)be a switch separate from the public spa's timing device,
(b)activate an audible and a visual signal when used, and
(c)have an emergency sign conforming to Sentence 3.11.10.1.(14).
(5)If a public spa and public pool are located in the same room or space, the emergency stop buttons required in Sentences (3) and 3.11.10.1.(12) shall deactivate all pumps serving the public spa and public pool.
Open OBC Div. B 3.12.5.1. in the code viewer

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OBC Div. B 3.13.1.2. Definitions
(1)In this Section:
Ancillary space means the rooms or spaces in the station used only by the transit agency to house or contain operating, maintenance or support equipment and functions, but does not include booths and kiosks used by the transit agency or service rooms.
Central supervising station means the operations centre where the transit agency controls and co-ordinates the system-wide movement of passengers and vehicles and from which communication is maintained with supervisory and operating personnel of the transit agency and with participating agencies when required.
Crush load means the total of the seating capacity and the standing capacity of a car where
(a)the seating capacity is the number of seats in a car, and
(b)the standing capacity is 0.2 m² per person for the standing area which is measured 300 mm in front of the seats.
Egress capacity means the number of people able to travel from or through a type of egress facility in a specified period of time.
Entraining load means the number of passengers boarding the train at a station.
Fare paid area means that portion of a rapid transit station to which access is gained by a pass or by paying a fare.
Fare-paid area control means the point where passengers enter or leave the fare paid area.
Link load means the number of passengers on board the train(s) travelling between two stations.
Maximum calculated train load means the crush load per car multiplied by the maximum number of cars per train in the peak period.
Peak direction means, for each route, the direction of train travel having the largest passenger flow volume based on the sum of the incoming link load plus the entraining load per peak hour.
Protected route means that portion of a means of egress that starts at the point where passengers would not be vulnerable to exposure from a train fire and that leads to the exterior of the station or through an exit to an adjacent building.
Public area means the public circulation areas in a rapid transit station providing pedestrian access to and from trains.
Rapid transit station means a building or part thereof used for the purpose of loading and unloading passengers of a rapid transit system but does not include open air shelters at street level.
Rapid transit system means an electrified transportation system, utilizing guidance methods involving positive mechanical contact with the fixed way operating on a right-of-way for the mass movement of passengers.
Open OBC Div. B 3.13.1.2. in the code viewer
OBC Div. B 3.13.3.7. Emergency Lighting
(1)Emergency lighting shall be provided to average levels not less than 10 lx at floor or tread level in public areas in a rapid transit station.
(2)An emergency power supply conforming to Subsection 3.2.7. shall be provided to maintain the emergency lighting required in Sentence (1) for a period of 30 min after a power failure.
Open OBC Div. B 3.13.3.7. in the code viewer
OBC Div. B 3.13.5.1. Fire Alarm System
(1)Except as provided in this Subsection, a fire alarm system conforming to Subsection 3.2.4. shall be installed in a rapid transit station.
Open OBC Div. B 3.13.5.1. in the code viewer
OBC Div. B 3.13.7.1. Application
(1)Every rapid transit station shall be provided with an emergency ventilation system conforming to NFPA 130, "Standard for Fixed Guideway Transit and Passenger Rail Systems."
Open OBC Div. B 3.13.7.1. in the code viewer
OBC Div. B 3.14.1.10. Electrical Systems
(1)The electrical system and equipment in a tent, including electrical fuses and switches, shall be inaccessible to the public.
(2)Cables on the ground in areas used by the public in a tent shall be placed in trenches or protected by covers to prevent damage from traffic.
Open OBC Div. B 3.14.1.10. in the code viewer
OBC Div. B 3.14.2.7. Electrical Systems
(1)The electrical system and equipment in an air-supported structure, including electrical fuses and switches, shall be inaccessible to the public.
(2)Cables on the ground in areas used by the public in an air-supported structure shall be placed in trenches or protected by covers to prevent damage from traffic.
Open OBC Div. B 3.14.2.7. in the code viewer
OBC Div. B 3.14.2.6. Emergency Air Supply
(1)An air-supported structure designed for an assembly occupancy with an occupant load of more than 200 persons shall have either an automatic emergency engine-generator set capable of powering one blower continuously for 4 h, or a supplementary blower powered by an automatic internal combustion engine.
Open OBC Div. B 3.14.2.6. in the code viewer
OBC Div. A 1.4.1.2.(1) Shelf and rack storage system
Shelf and rack storage system means a self-contained structural system within a building, having one or more elevated platforms or walkway levels for personnel access that may also support conveyors and other material handling, storage and distribution equipment.
Open OBC Div. A 1.4.1.2.(1) in the code viewer
OBC Div. B 3.16.1.5. Lighting
(1)Walkways and platforms shall be equipped to provide illumination to an average level not less than 50 lx at floor or tread level and at angles and intersections at changes of level where there are stairs or ramps.
(2)Emergency lighting on walkways, platforms, unenclosed egress stairs and exits providing means of egress shall conform to not less than
(a)the illumination level in Sentences 3.2.7.3.(2) and (3), and
(b)the duration in Sentence 3.2.7.4.(1).
Open OBC Div. B 3.16.1.5. in the code viewer
OBC Div. B 3.16.1.6. Sprinkler System
(1)An automatic sprinkler system conforming to this Article shall be installed in a floor area containing a shelf and rack storage system.
(2)The automatic sprinkler system shall be designed, constructed, installed and tested in conformance with NFPA 13, "Standard for the Installation of Sprinkler Systems" or the appropriate NFPA sprinkler standard for the most severe hazard to which the storage system is exposed.
(3)Sprinkler protection shall be provided under all platforms and walkways.
(4)Except where the platforms or walkways are of open construction, any openings for egress stairs shall be protected by noncombustible draft stops not less than 450 mm below the floors above.
(5)The automatic sprinkler system shall be electrically supervised to indicate a trouble signal on the building fire alarm system annunciator or where the building does not have a fire alarm system, to notify the person controlling the operation of the building for each of the situations listed in Sentence 3.2.4.9.(3).
(6)The automatic sprinkler system shall be designed to notify the fire department that a waterflow switch has been activated.
(7)The notification to the person controlling the building and the fire department referred to in Sentences (5) and (6) shall be provided in accordance with Sentence 3.2.4.7.(4).
(8)A permanent sign shall be posted, at or near the sprinkler control valve, containing
(a)the word notice in contrasting letters,
(b)a description of the commodity class as defined in NFPA 13, "Standard for the Installation of Sprinkler Systems," and
(c)the sprinkler design criteria used for the shelf and rack storage system.
Open OBC Div. B 3.16.1.6. in the code viewer
OBC Div. B 3.18.1.1. Application
(1)This Section applies where proposed construction
(a)in respect of an existing building will result in any of the following changes of use of all or part of the building:
(i)a change of the major occupancy of all or part of a building that is designated with a "Y" in Table 1.3.1.4. of Division C,
(ii)a suite of a Group C major occupancy is converted into more than one suite of a Group C major occupancy,
(iii)a suite or part of a suite of a Group A, Division 2 or a Group A, Division 4 major occupancy is converted to a gaming premises,
(iv)a farm building or part of a farm building is changed to a major occupancy,
(v)a building or part of a building is changed to a post-disaster building,
(vi)a building or part of a building is changed to a retirement home, or
(vii)the use of a building or part of a building is changed and the previous major occupancy of the building or part of the building cannot be determined, or
(b)in respect of an existing building of combustible construction will extend the building by adding a storey or storeys such that the extended building will be more than four storeys in building height.
(2)For the purposes of this Section and Sentences 11.4.2.1.(1) and 11.4.2.5.(4), the changes of use set out in Subclauses (1)(a)(ii) to (iv) and (vi) shall also be deemed to constitute a change in major occupancy.
(3)The requirements of this Section are in addition to the requirements of other Parts of this Division as they apply to the proposed construction.
Open OBC Div. B 3.18.1.1. in the code viewer
OBC Div. B 3.18.2.1. Change of Use and Compensating Construction
(1)Where proposed construction will result in a change of use described in Subclauses 3.18.1.1.(1)(a)(i) to (iv) and (vi), additional construction shall be required in order that the building or part of a building subject to the change of use conforms to the requirements of Subsection 3.2.6. and Sections 3.7., 3.11. and 3.12. as they apply to the new major occupancy that the building or part of a building is to support.
(2)For the purposes of this Article, existing buildings shall be classified as to their construction and occupancy as provided for in Sentence 11.2.1.1.(1).
Open OBC Div. B 3.18.2.1. in the code viewer
OBC Div. B 3.18.2.2. Performance Level and Compensating Construction
(1)The performance level of a building after construction shall not be less than the performance level of the building prior to construction.
(2)For the purposes of Sentence (1), reduction of performance level shall be determined in accordance with Articles 11.4.2.1., 11.4.2.3., 11.4.2.5. and 11.4.2.6.
(3)Where proposed construction would reduce the performance level of an existing building, compensating construction shall be required in conformance with Articles 11.4.3.1., 11.4.3.2., 11.4.3.4., 11.4.3.6. and 11.4.3.7.
(4)Section 11.5. applies in respect of the requirements of Sentences 11.4.3.4.(1), (3) and (4).
Open OBC Div. B 3.18.2.2. in the code viewer