After my recent article on the subject of consistency between the National Building Code of Canada (NBCC) and certain codes and standards referenced by the NBCC, I have received a few e-mails with expressions of frustration and with questions from the readers regarding potential conflict between the NBCC and the Elevator Code ASME A17/CSA B44 harmonized between the USA and Canada.
The main concerns related to the potential conflict between these two documents were expressed by the electrical designers, contractors and inspectors in respect to specific requirements for electrically connected life safety devices and equipment.
So, let’s illustrate some of these concerns in a few examples as follows:
Emergency Operation and Signalling Devices
1. Section 2.27 of the Elevator Code - CSA standard B44 covers "Emergency Operation and Signalling Devices.”
Note in the Elevator Code states the following: "additional requirements, including those for fire-fighters’ communication systems, may be found in the building code.”
Subsection 2.27.1 provides requirements for "Car Emergency Signalling Devices.” It is interesting to review the language of Clauses 18.104.22.168.1 and 22.214.171.124.2 for their consistency with the NBCC (with the document that might have additional requirements, as indicated in Note on Section 2.27).
Clause 126.96.36.199.1 requires that "A two-way communication means between the car and a location staffed by authorized personnel shall be provided.” This Clause is silent on the specifics where actually such "location staffed by authorized personnel shall be provided.” Before we’ll explore the provisions of the NBCC in this regard, let’s take a look at Clause 188.8.131.52.2 that continues to address two-way communication requirements between the elevator car and the location staffed by authorized personnel. This Clause mandates that:
(a) Two-way communications shall be directed to a location(s) staffed by authorized personnel who can take appropriate action;
(b) If the call is not acknowledged within 45 s, the call shall be automatically directed to an alternate on- or off-site location.
Some users of the Elevator Code are under the impression that such "location staffed by authorized personnel” must be provided in the building equipped with an elevator. However, in reality, it is impracticable to expect such staffed location in a typical 3 or 5 storey residential or office building or even in an office or residential hi-rise building where dedicated authorized concierge or security staff does not exist.
Now is the appropriate time to find out what the NBCC mandates on this subject. Sentence 184.108.40.206.(2)(j) of the NBCC states that the Central Alarm and Control Facility (or CACF in abbreviated form) installed in a building must be provided with "means to communicate with telephones in elevator cars, separate from connections to firefighters’ telephones, if elevator cars are required by CSA B44,” Safety Code for elevators, "to be equipped with a telephone.” But what does Central Alarm and Control Facility or CACF mean? And is the NBCC requirement for a CACF applicable for every building?
The review of the NBCC clearly demonstrates that a CACF is a very specific infrastructure of equipment and controls dedicated to supervisory, annunciating, control and communication functions that must be provided on the storey containing the entrance for the fire respondents to the building, and that such CACF is only required to be installed in buildings that are defined by the NBCC as "high buildings.” In all other buildings, installation of a CACF is not required by the NBCC, and of course ability to establish "location staffed by authorized personnel” in a building is not practicable for majority of building projects. So, does this particular example mean that the Elevator Code requirements are in conflict with the NBCC?
Not necessarily. The B44 requirement that "location staffed by authorized personnel shall be provided” simply means that the designers should specify a need for a communication between telephones in the elevators cars and a central station that monitors building fire alarm system (or between telephones in the elevator cars and any other communication facility staffed with authorized personnel).
The objective of this Elevator Code requirement is to articulate a need to receive the signal from elevator cars telephones, to process it and to respond to this call by the authorized personnel of the staffed communication facility, when a person in distress located in the elevator picks up the elevator car phone and makes this call. Unfortunately, some designers overlook this requirement of the B44, and some AHJs never audit compliance with this requirement during a coordinated life test or during the test of the elevator operation.
Emergency Recall Operation
2. Clause 220.127.116.11.2 of the B44 mandates the following requirements for Phase I Emergency Recall Operation of Elevators by Fire Alarm Initiating Devices.
18.104.22.168.2 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 floor served by the elevator
(b) in the associated elevator machine room, machinery space containing a motor controller or electric driving machine, control space or control room.
Perhaps, to re-phrase this requirement, it is appropriate to mention the following: B44 simply states that if an elevator equipped with the automatic emergency recall feature is installed in any building (regardless of the building height or building occupancy classification), at least one smoke detector must be provided in the elevator machine room and at each floor in the elevator lobby served by this elevator — in order to initiate automatic emergency recall operation of the elevator to the recall level.
It should be noted that the number of smoke detectors that have to be located in each specific area where smoke detectors are mandated by the Elevator Code or by the NBCC should be determined based on provisions of the ULC S524 (One smoke detector usually covers an area not exceeding 81 sq. m.). It is also interesting to note that this particular B44 requirement references the NBCC as the Code that mandates installation of smoke detectors in those specific locations (see italicized portion of the quoted Clause 22.214.171.124.2 above).
Now is the perfect opportunity to review the NBCC provisions in this regard.
The 2010 edition of the NBCC has been revised to reflect the Elevator Code requirements for the automatic emergency recall of elevators by dedicated smoke detectors. However, despite new NBCC revisions on this subject, a full consistency of the NBCC with the Elevator Code has not been achieved.
New Sentence 126.96.36.199.(1)(g) of the NBCC mandates installation of smoke detectors in elevator machine rooms.
New sentence 188.8.131.52.(4) of the NBCC states the following: "184.108.40.206.(4) Smoke detectors required by Clause (1)(g) shall, upon actuation, recall the elevators served by the elevator machine room in which the smoke detector is installed.” So far, so good. It looks like there is a consistency between the B44 and NBCC on this matter. But, what about the B44 requirement for installation of smoke detectors at each floor, in order to initiate automatic emergency recall of the elevators serving the elevator lobby of the floor where the smoke detector is actuated? Unfortunately, the expected consistency between these two codes has not happened. Article 220.127.116.11. of the NBCC offers the following requirement in this regard:
18.104.22.168. Elevator Emergency Recall
(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 recall feature required by Sentence (1) is not required if the floor area containing the recall level is sprinklered throughout.
As it can be seen from the above NBCC provision, it does not match the B44 requirement for unconditional installation of smoke detectors in an elevator lobby at each floor of any building where elevators are provided, and these elevators are equipped with the automatic emergency recall feature.
Some local building codes try to match the B44 provisions by revising requirements for actuation of the automatic emergency recall of elevators by the smoke detectors installed in the elevator lobbies.
For example, the Vancouver Building By-Law (VBBL) has been revised accordingly to mandate such automatic emergency recall of the elevators. However, such revision in the VBBL is limited only to the elevators installed in high buildings covered by provisions of Subsection 3.2.6. as follows (it should be noted that only relevant provisions of Article 22.214.171.124. of the VBBL are quoted below):
126.96.36.199. Emergency Operation of Elevators
(1) Automatic and manual emergency recall shall be provided for all elevators serving storeys above the first storey.
(5) The automatic emergency recall requirement in Sentence (1) shall be activated by
(a) smoke detectors installed in each floor area in front of the elevator or elevators, or
(b) the building fire alarm system.
(6) Where smoke detectors, as provided by Sentence (5), are activated on the recall level a signal shall automatically direct the elevator to an alternate floor level.
(7) Smoke detectors in Sentences (5) and (6) shall be designed shall be designed as part of the building fire alarm system
So, what should a designer do in light of such inconsistency between the NBCC and B44?
In my view, the provisions of B44 should be utilized in the electrical design, as these B44 provisions (although not necessarily consistent with the Building Code) do not in a conflict with the NBCC, but simply supplement the NBCC as the additional fire safety requirements.
Fire Detectors in Elevator Shafts or Pits
3. What about the requirements to install fire detectors in the elevators shafts or elevator pits?
Sentence 188.8.131.52.(2)(e) of the NBCC clarifies the requirement for fire detection in an elevator shaft by stating that a fire detector (a smoke detector or a heat detector) must be located in an elevator hoistway. Sentence 184.108.40.206.(4) of the NBCC explains that if an elevator hoistway is sprinklered, then the fire detectors mandated by Sentence (2) are not required. This means that a separate flow detecting device (a dedicated flow switch) must be provided for a sprinkler system installed in the elevator hoistway; as in accordance with Article 220.127.116.11. of the NBCC, a flow switch monitoring a sprinkler system on a typical floor must be installed so that such flow switch covers a sprinkler system for the area not exceeding that particular floor.
However, the NBCC or the B44 do not mandate installation of fire detectors in an elevator pit. In fact, practice of installation of fire detectors in elevators pits has demonstrated numerous problems with the operation and maintenance of these fire detectors, and voluntary installation of fire detectors in elevator pits would be inconsistent with good engineering design and good engineering practice.
Lighting Requirements for Specific Areas
4. And what about lighting requirements for specific areas related to elevators? The NBCC does not provide any particular guidance in this regard.
Nevertheless, Clause 18.104.22.168 of the Elevator Code states that "Permanently installed electric lighting shall be provided in all machinery spaces, machine rooms, control spaces, and control rooms.” After making this profound statement by listing all the areas where lighting is required, the B44 confuses the Code users in Clause 22.214.171.124 that governs provisions for Electrical Equipment and Wiring, as this Clause states the following (see italicized portion of the Clause below):
126.96.36.199 Only such electrical wiring, raceways, cables, coaxial wiring, and antennas used directly in connection with the elevator, including wiring for signals, for communication with the car, for lighting, heating, air conditioning, and ventilating the car, for fire detecting systems, for pit sump pumps, and for heating and lighting the hoistway and/or the machinery space, machine room, control space, or control room shall be permitted to be installed inside the hoistway, machinery space, machine room, control space, or control room.
It looks like the B44 Clause that governs only the electrical equipment and wiring inadvertently implies that the elevator hoistway must be provided with lighting as well (in addition to the locations listed in Clause 188.8.131.52).
So, the examples illustrated above demonstrate that some aspects of the B44 and the NBCC are not necessarily in conflict, but other provisions of these codes could create a problem to the users if the inconsistent requirements in both codes are not discussed with the applicable AHJs before design and installation are completed.
Therefore, as usual, the relevant authorities with the jurisdictional power for administration of the B44 and the NBCC must be consulted at the design stage of any electrical project.
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