Inconsistencies between codes and standards

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Inconsistencies between codes and standards

After I wrote a couple of articles on this subject in my role as Chair of the Liaison S/C between the Canadian Electrical Code, Part I (CE Code) and the National Building Code of Canada (NBC), I have received numerous e-mails and phone calls from the electrical industry stakeholders with comments, observations, questions, and concerns.

The majority of such e-mails and phone calls came from the members of the electrical design/consulting community, and this fact is not surprising.

While the electrical contractors and electrical inspectors know and understand the relevant provisions of the NBC for application of the electrically connected life safety systems, electrical contractors and electrical inspectors don’t usually deal with these provisions, as the first group (electrical contractors) obtain electrical permits for installation of the electrical equipment in conformance with the legally adopted CE Code, and the second group (electrical inspectors) enforce compliance of electrical installations with the legally adopted CE Code in their particular jurisdictions.

Thus, the relevant provisions of the NBC regarding fire alarm systems, fire pumps, emergency generators, exit signs, emergency lighting, hold open devices, electromagnetic locks, interlocks of the fire alarm systems with the emergency recall of elevators quite often remain outside the scope of responsibilities assigned to the electrical contractors and to the electrical inspectors.

Of course, electrical contractors are intimately involved in installation of such electrically connected life safety systems, but their involvement is based on the fact that such systems are specified by the electrical designers and are shown on the electrical plans produced by the electrical designers. This latter condition means that the electrical designers do not have luxury of ignorance on the NBC provisions for electrically connected life safety systems.

As the result, electrical consultants/electrical designers always use Appendix G of the CE Code, which provides a useful cross-reference between the CE Code and the NBC, and the members of the electrical consulting community are well versed on the NBC requirements for electrically connected life safety systems. This is the reason that the electrical consultants usually raise numerous questions and concerns regarding lack of clarity in the NBC (or regarding the inconsistency of the NBC with the CE Code) on the subject of electrically connected life safety systems.

For the purpose of this discussion, the 2015 edition of the NBC and 2018 edition of the CE Code will be referenced.

Inconsistencies between codes and standardsBefore presenting a few examples of such inconsistency or lack of clarity, let’s start with the CE Code Appendix G.

Introduction and application of this Appendix to the CE Code users states as follows:

“G1 Introduction
G1.1
This Appendix lists requirements related to electrical installations that are not governed by Rules of the Canadian Electrical Code, Part I but are required by the National Building Code of Canada.
G1.2
References listed in this Appendix are associated with electrical installations that are a part of the fire protection requirements contained in the National Building Code of Canada.

“G2 Application
G2.1
The intent of this Appendix is to advise Canadian Electrical Code, Part I users of performance requirements for electrically connected fire-protective equipment required by the National Building Code of Canada.
G2.2
Special fire protection requirements, such as use of thermal insulation, fire spread, flame spread requirements for electrical wiring and cables, flame-spread requirements for combustible raceways, and construction of electrical equipment vaults are covered by this Code (e.g., Rules 2-126, 2-128, 2-130, 2-132, 26-354, etc.).
G2.3
Provincial and municipal building codes may deviate from the National Building Code of Canada, and users of this list should also check those codes.”

This Appendix helps the electrical designers to find the relevant provisions of the NBC and apply these provisions in their design of electrically connected life safety systems.

When the electrical designers apply the relevant NBC requirements for electrically connected life safety systems, these professionals represent the obvious group on the NBC users, who justifiably raise concerns and questions regarding inconsistency of the NBC with the CE Code or with other applicable standards, or regarding lack of clarity on application of the NBC requirements for electrically connected life safety systems.

Quite often such inconsistency creates tangible practical problems, as enforcement of the legally adopted NBC is per-formed by a wide range of authorities having jurisdictions (i.e., by the building inspection departments, sometimes by the fire inspection departments and, occasionally, by the electrical inspections departments), and the enforcement approach of the NBC regarding electrically connected life safety systems, appears to be far from being uniform.

Now, let’s show 8 examples (eight – should be enough) of such inconsistency or lack of clarity:

1. NBC requirements for penetration of fire rated assemblies.
Article 3.1.9.2. of the NBC states the following:
“3.1.9.2. Combustibility of Service Penetrations
1) Except as permitted by Articles 3.1.9.3. and 3.1.9.5., pipes, ducts, electrical outlet boxes, totally enclosed raceways or other similar service equipment that penetrate an assembly required to have a fire-resistance rating shall be noncombustible, unless the assembly was tested incorporating that service equipment. (See Note A-3.1.9.2.(1).)
Thus, if the housing of a recessed lighting fixture (luminaire) is constructed of noncombustible material in conformance with the CSA safety standard for luminaires (with CSA C22.2 No. 250.0), then installation of such recessed luminaire in a fire rated ceiling, should not be subjected to the provisions of Articles 3.1.9.2., as such housing is “noncombustible”, (i.e., is constructed of metal), and in accordance with Article 3.1.9.2., such housing would be permitted to penetrate the assembly required to have a fire resistance rating.

However, the NBC defines “noncombustible material” as follows “Noncombustible means that a material meets the acceptance criteria of CAN/ULC-S114, Test for Determination of Non-Combustibility in Building Materials,” and some building inspectors disregard the statement of the standard for luminaires that the housing is constructed of noncombustible material and mandate that the electrical contractors and electrical designers must demonstrate that a noncombustible housing of a recessed luminaire constructed in conformance with the CSA standard C22.2 No. 250.0 does, in fact, represent a noncombustible material that meets CAN/ULC S114 test in accordance with the NBC definition.

This approach is often used by the building inspectors in respect to a recessed panelboard in a metal (noncombustible) enclosure, a recessed mounted metal (noncombustible) enclosure of an emergency phone, or even to a metal (noncombustible) outlet box, only because the definition “noncombustible” of the NBC does not appear to be consistent with the definition of the CE Code.

Thus, the electrical designers and the electrical contractors who use the appropriate requirements of 30-900 series Rules of the CE Code (see below) when a recessed luminaire/recessed lighting fixture with a noncombustible housing is intended to be installed in “an assembly required to have a fire-resistance rating,” have to be prepared for a very unpleasant surprise from the perspective of the NBC.

“Recessed luminaires (see Appendix G)
30-900 General
Rules 30-900 to 30-912 apply to the installation of
luminaires recessed in cavities in ceilings or walls.

30-902 Spacings for Non-IC type luminaires
Except as provided for in Rules 30-904 and 30-908, the recessed portion of every recessed luminaire marked “Type Non-IC” shall be at least 13 mm from combustible material at every point other than the point of support, and thermal insulation shall not be installed closer than 76 mm to the luminaire.

30-904 Spacings for Non-IC — Marked spacings
type luminaires
The recessed portion of every recessed luminaire marked “Type Non-IC, marked spacings” shall be installed to maintain a minimum spacing from thermal insulation and combustible material at every point other than the point of support in accordance with the manufacturer’s spacings marked on the luminaire.

30-906 Luminaires designed for thermal insulation contact
The recessed portion of every recessed luminaire marked “Type IC” or “Type IC, inherently protected” shall be permitted to be in contact with combustible material or blanketed with thermal insulation.

30-908 Luminaires designed for non-combustible
surfaces contact only
A recessed luminaire marked as suitable for installation on a non-combustible surface shall be installed only on a non-combustible material.”

It should be noted that a request has been submitted on behalf of the CE Code/NBC Liaison S/C to the National Research Council of Canada (NRC) which looks after the NBC development – to correlate the NBC with the CE Code accordingly.

2. NBC requirements for protection of electrical conductors against exposure to fire.
Article 3.2.7.10. of the NBC requires that certain conductors supplying electrically connected life safety systems must be protected against exposure to fire.

Sentence 3.2.7.10.(1) of the NBC states the following:
“3.2.7.10. Protection of Electrical Conductors
1) The protection of electrical and emergency conductors referred to in Clauses (a) to (c) shall conform to the requirements stated in Sentences (2) to (11):
a) electrical conductors located within buildings identified in Article 3.2.6.1. serving
i) fire alarms,
ii) emergency lighting, or
iii) emergency equipment within the scope of Articles 3.2.6.2. to 3.2.6.8.”
This means that riser conductors of a fire alarm system and of emergency lighting and conductors supplying very specific equipment listed in Articles 3.2.6.2. to 3.2.6.8., must be protected by one of the options listed in Sentence 3.2.7.10.(2).

Sentence 3.2.7.10.(2) of the NBC describes the options under which such protection can be accomplished – by selecting circuit integrity rated conductors (tested to ULC S139) or by placing such life safety conductors in dedicated 1 h rated service spaces (service shafts) as follows:
“(2) Except as otherwise required by Sentence (3) and permitted by this Article, electrical conductors that are used in conjunction with systems identified in Sentence (1) shall
a) conform to CAN/ULC-S139, “Fire Test for Evaluation of Integrity of Electrical Power, Data and Optical Fibre Cables,” including the hose stream application, to provide a circuit integrity rating of not less than 1 h (see Note A-3.2.7.10.(2)(a) and (3)(a)), or
b) be located in a service space that is separated from the remainder of the building by a fire separation that has a fire-resistance rating not less than 1 h.”

Option (a) allows the electrical designers to specify circuit integrity cables which have been tested to the ULC standard S139.
However, Sentence 3.2.6.5.(6) which deals with protection of conductors supplying fire fighters’ elevators requires a different test methods for the cables supplying this elevator (see below):
“3.2.6.5.(6) Electrical conductors for the operation of the elevator referred to in Sentence (1) shall be
a) installed in service spaces conforming to Section 3.6. that do not contain other combustible material, or
b) protected against exposure to fire from the service entrance of the emergency power supply, or the normal service entrance of the normal power supply, to the equipment served, to ensure operation for a period of 1 h when subjected to the standard fire exposure described in CAN/ULC-S101, ‘Fire Endurance Tests of Building Construction and Materials,’ [see Note A-3.2.6.5.(6)(b)].”

This means that the requirement of Clause 3.2.6.5.(6)(b) above is in a conflict with the provision of Sentence 3.2.7.10.(2)(a), and the electrical designers who decide to specify a circuit integrity cable, become confused to which ULC standard for fire tests this cable would have to be tested.

When the option (b) above is used by the design, it means that only conductors required to be protected by the NBC, are allowed to be placed into a service shaft with a fire resistance rating of not less than 1 h.

However, this NBC requirement does not take into account that where life safety systems described in Article 3.2.7.10. are installed in a health care facility, such life safety systems become part of the health care facility “essential electrical system,” and that Rule 24-302(1) of the CE Code specifically describes such situation in the following requirements for the essential electrical system loads:

“24-302 Circuits in essential electrical systems
(see Appendix B)
1) An essential electrical system shall consist of circuits that supply loads designated by the health care facility administration as being essential for
a) life safety in accordance with Section 46;
b) care of the patient; and
c) effective operation of the health care facility.”

As it is mentioned above, the NBC is silent on essential electrical system, and Article 3.2.7.10. is only limited to protection of life safety system conductors. So, there appears to be a gap in correlation between the NBC and the CE Code on this subject. It should be noted that Section 24 of the CE Code and of the CSA standard Z32 – both treat all essential electrical systems equipment (including conductors that supply them) in an identical manner.

Thus, quite often, when such fire rated service shafts are used in a health care facility, where life safety conductors must be protected against exposure to fire, the electrical designers have to ensure that conductors supplying (let’s say) essential systems required for performance of vital ICU equipment or vital loads in an operating room, are physically separated from the life safety conductors (i.e., such conductors of the essential electrical system that supply loads vital to the care of patients) are installed in separate service shafts than the conductors of the life safety system. Such design approach forces installation to be significantly more expensive without any benefit to the electrical and fire safety and to the performance of the essential electrical system.

It should be noted that the proposal has been submitted for the amendment of Article 3.2.7.10. of the NBC to clarify that provisions of Article 3.2.7.10. also apply to all conductors of the essential electrical system in a health care facility (HCF), when such HCF is located in a high building as described by the NBC.

3. NBC requirements for location of smoke
detectors in elevator lobbies.
Article 3.2.4.14. of the NBC states the following:
“3.2.4.14. Elevator Emergency Return
1) Except as permitted by Sentence (3), in a building having elevators that serve storeys above the first storey and that are equipped with an automatic emergency recall feature, smoke detectors shall be installed in the elevator lobbies on the recall level so that when these smoke detectors are actuated, the elevators will automatically return directly to an alternate floor level.
2) Smoke detectors required by Sentence (1) shall be designed as part of the building fire alarm system.
3) The alternate floor recall feature required by Sentence (1) is not required if the floor area containing the recall level is sprinklered throughout.”

The above stated NBC requirement appears to be very clear. It mandates installation of smoke detectors in the elevator lobbies on the recall level only. It means that the smoke detectors must be installed in a lobby served by an elevator on the recall floor only, so when any of such dedicated smoke detectors is actuated, an automatic recall feature of the elevator will initiate elevator recall to an alternative level.
However, the electrical designers who did not venture to read relevant provisions of the CSA standard B44 “Safety Code for Elevators and Escalators”, would be in for a big surprise, as B44 mandates a bit different requirement in this regard in Clause 2.27.3.2.2. as follows:
2.27.3.2.2. In jurisdictions enforcing the NBCC, smoke detectors, or heat detectors in environments not suitable for smoke detectors (fire alarm initiating devices), used to initiate Phase I Emergency Recall Operation, shall be installed in conformance with the requirements of the NBCC, and shall be located
(a) at each elevator lobby served by the elevator
(b) in the associated elevator machine room, machinery space containing a motor controller or driving machine, control space, or control room
(c) in the elevator hoistway, when sprinklers are located in those hoistways.”

This B44 requirement means that the dedicated smoke detectors intended to initiate elevator automatic emergency recall, must be installed in the elevator lobby on each floor (and not only at the floor of the recall level), in an elevator machine room, in a “machinery space containing a motor controller or driving machine, control space, or control room” and in a sprinklered elevator hoistway.
Needless to say, it should be noted that the NBC has a similar provision for smoke detectors, and this provision is only extended to the elevator machine room [see Sentence (1)(g) and (4) below]:

“3.2.4.11. Smoke Detectors
(1) ……………….
g) elevator machine rooms.
(See Note A-3.2.4.11.(1) )
(4) Smoke detectors required in Clause (1)(g) shall, upon actuation, recall the elevators served by the elevator machine room in which the smoke detector is installed.”

No doubt that such inconsistency between the B44 and the NBC (and lack of knowledge of this nonconsistency) might create a very measurable impact on cost of installation and on fire safety in the building.

It should be also noted by the readers that a proposal to amend the NBC – to remove such inconsistency, has been submitted to the NRC accordingly.

4. NBC permission of installation of smoke
detectors in lieu of smoke alarms.
Sentences 3.2.4.20.(8) and (9) allow the following:
“(8) Suites of residential occupancy are permitted to be equipped with smoke detectors in lieu of smoke alarms, provided the smoke detectors
a) are capable of independently sounding audible signals within the individual suites,
b) except as permitted in Sentence (9), are installed in conformance with CAN/ULC-S524, “Installation of Fire Alarm Systems,” and
c) form part of the fire alarm system.
(See Note A-3.2.4.20.(8).)
(9) Smoke detectors permitted to be installed in lieu of smoke alarms as stated in Sentence (8) are permitted to sound localized alarms within individual suites, and need not sound an alarm throughout the rest of the building.”

However, this relaxation appears to confuse the electrical designers on a need to provide a signal to the fire department (where signals to the fire department are required by Article 3.2.4.7. of the NBC) upon actuation of the smoke detectors used in lieu of smoke alarms, as Article 3.2.4.20. of the NBC is silent on this subject. It should be noted that a proposal to clarify this issue, has also been submitted to the NRC.

5. NBC requirement for electrical supervision of fire alarm systems.
Article 3.2.4.9. of the NBC mandates electrical supervision for a fire alarm system.

NBC also mandates compliance with ULC S524 for installation of fire alarm systems, and Clause 4.3 of ULC S524 provides comprehensive requirements for all aspects of the electrical supervision, including which components of a fire alarm system must be electrically supervised, what type of signals should be activated if a trouble or supervisory condition arises, and where such trouble and supervisory signals must be visually and audibly indicated (see below):
“4.3.1.2. Fire alarm system devices connected in an electrically supervised circuit shall be connected so that removal or disconnection of any device shall cause a trouble signal to be initiated
4.3.2.1. A common audible and visible trouble signal shall be provided and located at each control unit, annunciator and display and control centre”

Thus, it is expected that any supervisory condition will be manifested by a specific trouble signal at a fire alarm system annunciator and at a central station conforming to ULC S561, as required by Sentence 3.2.4.7.(4) of the NBC. Thus, the requirement of Sentence 3.2.4.9.(5) of the NBC appears to conflict with provisions of ULC S524 and with Article 3.2.4.7. of the NBC.

This fact confuses the electrical designers, as Sentence 3.2.4.9.(5) of the NBC mandates that a supervisory signal for any supervisory (and not for a fire alarm) condition on a sprinkler system, must be transmitted not to the central station, but to the fire department (see below):
“3.2.4.9.(5) Indication of a supervisory signal in accordance with Sentence (3) shall be transmitted to the fire department in conformance with Sentence 3.2.4.7.(4).”

It should be noted that some local building by-laws (for example – Vancouver Building By-Law) have been amended so, as to mandate a transmission of any supervisory condition listed in Sentence 3.2.4.9.(3) to the central station, instead of to the fire department. It should be also noted that a respective proposal for the NBC amendment was also submitted to the NRC.

6. NBC requirement of Article 3.2.4.18. for audibility of Alarm Systems.
Sentence 3.2.4.18.(1)(a) of the NBC appears to be quite clear for the new construction projects, when the audible signal devices are installed throughout the floor area (see below):
“3.2.4.18. Audibility of Alarm Systems
(1) Audible signal devices forming part of a fire alarm system shall be installed in a building so that
a) alarm signals are clearly audible throughout the floor area, and …..”

However, if the scope of the project includes installation of the new audible signal devices to the floor area, where the existing audible signal devices of the existing fire alarm system are located, all audible signal devices installed inside the referenced floor area must be clearly audible through that particular floor area and must provide a consistent sound pattern throughout that floor area, as required by Sentence 3.2.4.18.(1)(a) of the NBC. The electrical designers are concerned that the referenced NBC requirement does not provide an explanatory note to clarify that in some cases, where the sound pattern generated by the existing audible devices cannot be modified due to the existing technical restrictions, the newly installed audible signal devices under the scope of the addition project could be re-programmed – to mimic the existing sound pattern, as the existing fire safety in respect to the audibility sound pattern will not be compromised. These electrical designers make substantiated observations that the referenced NBC requirement was written with the objective that a clear audible sound will be produced through the entire floor area.

When the sound pattern of the alarm signal is different on the floor area from different audible signal devices located on the floor area, clarity of the intended audibility will be drastically reduced, and instead of the intended clear early warning signal, occupants will be subjected to unwarranted confusion.

These designers also point out the following provision of Clause 9.1.7 of ULC S524:
“9.1.7 Audible signal devices within a building shall generate similar sounds and sound patterns when activated” and indicate that lack of clarification on this subject in Article 3.2.4.18. of the NBC creates inconsistency in design, installation and enforcement of the fire alarm system audibility.

A similar issue relates to the requirement of Sentence 3.2.4.18.(6) of the NBC. This Sentence currently states the following:
“6) Except as required by Sentence (5), the sound pressure level from a fire alarm system’s audible signal device within a floor area shall be not less than 10 dBA above the ambient noise level without being less than 65 dBA”, and this Sentence does not appear to clarify to the NBC users, whether the audibility level not less than 65 dBA must be also met within every meeting room in a floor area of typical office, when doors of such meeting rooms are being closed.

As the result of such lack of clarity in the NBC, cost of installations across different jurisdictions varies drastically, as some AHJs apply provisions of Sentence 3.2.4.18.(6) above literally, and others – mandate the required audibility level to be achieved, when doors of such meeting rooms on the floor area are being closed.
The proposal has been submitted to the NRC for clarification of the referenced NBC requirement.

7. NBC requirement of Article 3.2.7.5. for the emergency power supply installation.
Article 3.2.7.5. of the NBC does not appear to be consistent with Rule 46-202(3)(c) of the CE Code.

The CE Code mandates that when a generator is used as the source of the emergency power supply, such generator must comply with the CSA standard C282 (see below):
“46-202 Types of emergency power supply (see Appendices B and G)
1) The emergency power supply shall be a standby supply consisting of
a) a storage battery of the rechargeable type having sufficient capacity to supply and maintain at not less than 91% of full voltage the total load of the emergency circuits for the time period required by the National Building Code of Canada, but in no case less than 30 min, and equipped with a charging means to maintain the battery in a charged condition automatically; or
b) a generator………
3) Where a generator is used, it shall be
a) of sufficient capacity to carry the load;
b) arranged to start automatically without failure and without undue delay upon the failure of the normal power supply to any transfer switch connected to the generator; and
c) in conformance with CSA C282.”

However, Article 3.2.7.5. of the NBC mandates that all emergency power supply systems must be installed in accordance with CSA C282, disregarding the fact, that other provisions of the NBC (e.g. Articles 3.2.7.4. and 3.2.7.8.) and Rule 46-202 of the CE Code allow use of batteries as a source of the emergency power for certain types of life safety systems. (see below):
“3.2.7.5. Emergency Power Supply Installation
(1) Except as required by Articles 3.2.7.6. and 3.2.7.7., an emergency electrical power supply system shall be installed in conformance with CSA C282, “Emergency Electrical Power Supply for Buildings.”

Of course, the proposal has been also sent to the NRC – to clarify this NBC requirement.

8. NBC requirement of Article 3.4.5.1. for circuitry supplying lighting for externally and internally illuminated exit signs.
Sentence 3.4.5.1.(5) appears to confuse the electrical practitioners, as the requirement of this Sentence is not consistent with Rule 46-400 of the CE Code.

Rule 46-400 of the CE Code requires that the electrically connected exit signs must be connected only to a dedicated electrical circuit, unless such circuit supplies emergency lighting in the area where such exit signs are installed (see below):

“46-400 Exit signs
(1) Where exit signs are connected to an electrical circuit, that circuit shall be used for no other purpose.
(2) Notwithstanding Subrule 1), exit signs shall be permitted to be connected to a circuit supplying emergency lighting in the area where these exit signs are installed”

However, Sentence 3.4.5.1.(5) of the NBC appears to be inconsistent with the CE Code, as this Sentence mandates that the circuitry supplying exit signs must serve no equipment other than emergency equipment (see below):
“3.4.5.1.(5) The circuitry serving lighting for externally and internally illuminated exit signs shall
a) serve no equipment other than emergency equipment, and
b) be connected to an emergency power supply as described in Article 3.2.7.4.”

These few examples demonstrate that the NBC is far from being perfect, and that all stakeholders of the electrical industry who use the NBC, should try to improve consistency between the NBC and the CE Code.

Meanwhile, as usual, the relevant local Authorities Having Jurisdiction must be consulted for the interpretation on application of the NBC.


Ark Tsisserev is president of EFS Engineering Solutions, an electrical and fire safety consulting company, and is a registered professional engineer with a master’s degree in Electrical Engineering. Prior to becoming a consultant, Ark was the Chief Electrical Inspector for the City of Vancouver. He is the immediate past chair of the CSA TC for the CE Code, Part I and for the CSA Strategic Steering Committee for the Requirements of Electrical Safety. Ark also represents the CE Code Committee on the CMP-1 of the National Electrical Code. Ark can be reached by e-mail at: ark.tsisserev@efsengineering.ca
His company web site is www.efsengineering.ca

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