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EIABC - November 2015 Newsletter 
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Message from the President 

 
Hello fellow members, I hope everyone is enjoying the beautiful fall weather.

My message for this newsletter will be short but sweet.

We have our upcoming Christmas Dinner on Monday, November 23rd. This event is always well attended and a great event for networking and lively discussions. Due to catering needs we need to have firm numbers into the event staff by no later than Friday November 13thPlease visit our website to book and pay for your seats by this date. A $20 surcharge will be added to the cost of the ticket if you pay at the door.

Secondly, we are in the final preparations for our 2015 Code Update Seminar which will be held at the Telus Boot building at Kingsway and Boundary in Burnaby. The event will be held on Saturday, January 23rd in 2016.  Let all your contacts know of the event. We have the finest of instructors which include Ark Tsisserev, Ted Simmons, Carlo Turra and George Razzo. This event is also a fully catered event and we need to have the final numbers in by January 6th in order to facilitate this great event. If you note on our website the cost of the tickets go up the longer you wait and tickets are going fast. We only have a limited amount of seats so please get online and book your seats now.

Your executive board would like to thank you for your continued support of the association.  Please feel free to contact myself directly if you have any comments or concerns. The association is only as strong as its membership so please reach out to myself and let us know how great we are doing or if you would like to see a future subject discussed at one of our upcoming dinner meetings.

Thanks,
Jason Rowley
President  EIABC
president@eiabc.org

November 2015


Inside This Issue


Message from the President
- Jason Rowley


Hazardous Location? Confusion Still Exists
- Ark Tsisserev

EIA Code Article - November 2015
- Ted Simmons

 



EIA Executive
 

Electrical Inspectors Association of British Columbia

Suite 201, 3989
Henning Drive Burnaby,
B.C., V5C 6N5

Phone: 604-294-4123
Fax: 604-294-4120
Email: info@eiabc.org



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Hazardous Location? Confusion Still Exists

 
By Ark Tsisserev, P.Eng.
Ark Tsisserev is an independent electrical fire and safety 
consultant. Prior to becoming a consultant, he was an electrical safety regulator / Chief Electrical Inspector for the City of Vancouver . EFS Engineering Solutions Ltd. 
ark.tsisserev@efsengineering.ca

 


Two years ago this journal has published my article titled “Hazardous Location: How Do We Know That It Actually Is?”, and I received a number of positive observations on it.
With the changes to Section 18 in the 2015 edition of the Canadian Electrical Code, Part I (CE Code), I received a number of new comments and questions on installation of electrical equipment in hazardous locations. Majority of these questions relate to the following issues:
  1. Where to find the ultimate expertise for determination of a hazardous locations described in Section 18?
  2. Why atmospheres with hazardous concentrations of combustible dusts or ignitable fibres have disappeared from classification of hazardous locations in Section 18?
  3. Why Section 18 has abolished description of Classes of hazardous locations, but such description remains in other Sections of the Code?
  4. Why despite the fact that Section 18 has adopted classification of hazardous locations based on zones (and not on classes), electrical equipment in such location still has to be suitable for the appropriate Class and Division of hazardous location?
  5. What is the intent of Rule 18-068?
Let’s discuss these questions one-by-one and try to provide some clarification on them.
 
1. Where to find the ultimate expertise for determination of a hazardous locations described in Section 18?
Subrule 18-000(1) of the 2015 edition of the CE Code states the following:
“18-000 Scope (see Appendices B, F, and J)
(1) This Section applies to locations in which electrical equipment and wiring are subject to the conditions indicated by the following classifications.”


“Hazardous location” is defined in Section 0 of the CE Code as follows:
“Hazardous location (see Appendix B) — premises, buildings, or parts thereof in which
  • (a) an explosive gas atmosphere is present, or may be present, in the air in quantities that require special precautions for the construction, installation, and use of electrical equipment;
  • (b) combustible dusts are present, or may be present, in the form of clouds or layers in quantities to require special precautions for the construction, installation, and operation of electrical equipment; or
  • (c) combustible fibres or flyings are manufactured, handled, or stored in a manner that will require special precautions for the construction, installation, and operation of electrical equipment.”

Rule 18-002 of the CE Code “special terminology” offers the following classification of zones that compose (or make up) hazardous locations:
“Zone 0 — a location in which explosive gas atmospheres are present continuously or are present for long periods.
Zone 1 — a location in which
  • (a) explosive gas atmospheres are likely to occur in normal operation; or
  • (b) the location is adjacent to a Zone 0 location, from which explosive gas atmospheres could be communicated.
Zone 2 — a location in which
  • (a) explosive gas atmospheres are not likely to occur in normal operation and, if they do occur, they will exist for a short time only; or
  • (b) the location is adjacent to a Zone 1 location, from which explosive gas atmospheres could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided.
Zone 20 — a location in which an explosive dust atmosphere, in the form of a cloud of dust in air, is present continuously, or for long periods, or frequently.
Zone 21 — a location in which an explosive dust atmosphere, in the form of a cloud of dust in air, is likely to occur in normal operation occasionally.
Zone 22 — location in which an explosive dust atmosphere, in the form of a cloud of dust in air, is not likely to occur in normal operation but, if it does occur, will persist for a short period only.”


Rules 18-004 – 18-008 of the CE Code further elaborate on specifics of explosive atmospheres that might comprise a hazardous location (see below):

 “18-004 Classification of hazardous locations (see Appendices B, J, and L)
Hazardous locations shall be classified according to the nature of the hazard, as follows:
  • (a) explosive gas atmospheres; or
  • (b) explosive dust atmospheres.
18-006 Locations containing an explosive gas atmosphere (see Appendix B)
Explosive gas atmospheres shall be divided into Zones 0, 1, and 2 based upon frequency of occurrence and duration of an explosive gas atmosphere.

18-008 Locations containing an explosive dust atmosphere (see Appendix B)
Explosive dust atmospheres shall be divided into Zones 20, 21, and 22 based upon frequency of occurrence and duration of an explosive dust atmosphere”.


So far – so good. But how the CE Code user can determine whether concentration of these gases or dust in the air is, in fact, present in quantities that are sufficient to produce “explosive” gas or dust atmosphere? What if the Code user inaccurately assessed a potential for concentration of such explosive gases or dust in the air and has chosen to apply provisions of Section 18 for selection of electrical equipment and wiring methods where use of Section 18 is not warranted? And what if on contrary, the Code user has underestimated a potential for “explosive” gas or dust atmosphere in the air and did not apply requirements of Section 18 for the applicable selection of electrical equipment and wiring methods?

While a former approach will simply make installation unjustifiably more expensive, the latter approach will certainly make such installation unsafe and simply hazardous. Some Electrical Inspection Authorities do not necessarily have sufficient expertise – to assess whether the area in question could be, indeed, treated as a non-hazardous or ordinary location, and the inspectors prudently apply more restrictive approach – to ensure that the safety is not compromised, unless the determination of area classification is made by the process experts who are familiar with the relevant NFPA standards and with the appropriate provisions of the National Fire Code of Canada. However, who are the ultimate process experts on this subject, and does the CE Code address the criteria in accordance with which, such determination should be made? Appendix B

Note on Rule 18-000 of the CE Code offers the following information on this subject:
 “Appendix B Note on Rule 18-000
Through the exercise of ingenuity in the layout of electrical installations for hazardous locations, it is frequently possible to locate much of the equipment in a reduced level of classification or in a non-hazardous location and thus to reduce the amount of special equipment required.
To assist users in the proper design and selection of equipment for electrical installations in hazardous locations, numerous reference documents are available. Tables A, B, and C list the documents most commonly referenced”.


Is this information sufficient? Not really. Absence of information on this matter – in order to help the Code users consistently determine hazardous locations (and particularly accuracy in assessment of applicable Zones in a hazardous location) has created not only a huge void in clear understanding of the criteria for determination of the areas of hazardous locations, but it has become a subject of numerous arguments between various AHJ's, designers and installers.
It has been recognized in discussions between the CSA technical management and the members of the CSA Strategic Steering Committee on the Requirements for Electrical Safety that while the CE Code users clearly understand how to apply the requirements of Sections 18 for selection of electrical equipment and wiring methods for the determined hazardous areas,the electrical safety practitioners don't have sufficient expertise in understanding specific processes that can lead to the presence of explosive gas atmospheres. Thus, the CSA isconsidering to develop a guide that could be referenced by Section 18 of the CE Code and that could provide a basic assistance to the CE Code users in criteria for determination of hazardous locations. Meanwhile, only the process experts should be engaged in the determination of hazardous locations, and such process experts are not necessarily electrical engineers involved in electrical design.

2.  Why atmospheres with hazardous concentrations of combustible dusts or ignitable fibres have disappeared from classification of hazardous locations in Section 18?
As it was indicated in the discussion on question 1 above, Section 18 has been revised – to apply only to zone based classification of hazardous locations, and that Rule 18-004 classifies the nature of hazard based on presence of “explosive gas” or “explosive dust” atmospheres. However, definition of “dust” in Rule 18-002 (see below) also includes “combustible dust”,  “non-conductive dust” and “combustible flyings”:  
  • “Dust — generic term including both combustible dust and combustible flyings.
  • Combustible dust — dust particles that are 500 μm or smaller (material passing a No. 35 standard sieve as defined in ASTM E11) and present a fire or explosion hazard when dispersed and ignited in air.
  • Conductive dust — combustible metal dust.
  • Non-conductive dust — combustible dust other than combustible metal dust.
  • Combustible flyings — solid particles, including fibres, greater than 500 μm in nominal size that may be suspended in air and can settle out of the atmosphere under their own weight”.
Furthermore, definition of hazardous location in Section 0 (see discussion on question 1 above) includes “combustible dusts” and “combustible fibres and flyings”.
In addition, Appendix B Note on Rule 18-008 references “readily ignitable fibres and flyings”:

“Appendix B Note on Rule 18-008
Readily ignitable fibres and flyings include rayon, cotton (including cotton linters and cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fibre, oakum, baled waste kapok, Spanish moss, excelsior, and other materials of similar nature”.


So, for the purpose of Rule 18-004(b), “explosive dust atmospheres” include presence of “combustible or electrically conductive combustible dusts”, or “ignitable fibres or flyings” in air in quantities sufficient to produce “explosive dust atmosphere”, and the revision to Section 18 still recognizes the fact combustible dusts or ignitable fibres and flyings in air could become a source for an “explosive dust atmosphere”.

3.  Why Section 18 has abolished description of Classes of hazardous locations, but such description remains in other Sections of the Code?
It is true that certain Rules in Sections 20 and 22 still references Class and Zone location system. However, this fact is attributed to a simple editorial inaccuracy, and this inaccuracy has been noted by the Chairs of Sections 20 and 22 S/C’s and by the CSA editors accordingly, and the necessary changes will be made.

4.  Why despite the fact that Section 18 has adopted classification of hazardous locations based on zones (and not on classes), electrical equipment in such location still has to be suitable for the appropriate Class and Division of hazardous location?
The fact that the electrical equipment must be suitable for the appropriate Class and appropriate Division of a hazardous location has nothing to do with the revisions in Section 18 in the 2015 edition of the CE Code. Such requirements have existed in the 2012 edition (and in earlier editions) of the CE Code, as the CSA safety standards for electrical equipment (CSA Part II standards) may apply to equipment intended for use in hazardous locations based on “Class”  and “Division” classification. In fact, Appendix J18 of the CE Code is based on Class and Division type of classification of hazardous locations, and application of such classification is reflected in Subrules 18-000(3) and (4) as follows:

“Rule 18-000(3) For additions, modifications, renovations to, or operation and maintenance of existing facilities employing the Division system of classification, the continued use of the Division system of classification shall be permitted.
Rule 18-000(4) Where the Division system of classification is used as permitted by Subrule (3), the Rules for Class I, II, and III locations found in Annex J18 of Appendix J shall apply”.


It should be noted that Appendix B Note on Rule 18-000 also clarifies extent of application of electrical equipment “suitable” for Class and Division type classification of hazardous location under a Zone based classification system in Section 18(see below):

“Appendix B Note on Rules 18-000, 18-006, and 18-008
The Zone and Division systems of area classification are deemed to provide equivalent levels of safety; however, the Code has been written to give preference to the Zone system of area classification. It is important to understand that while the Code gives preference to the Zone system of area classification, it does not give preference to the IEC type of equipment. Equipment approved as Class I or Class I, Division 1 will be acceptable in Zone 1 and Zone 2, and equipment marked Class I, Division 2 will be acceptable only in Zone 2. See Rules 18-100 and 18-150 and the Table in Appendix J, Section J1.2.
The Scope of this Section recognizes that there are cases where renovations or additions will occur on existing installations employing the Class/Division system of classification. It is expected that such installations will comply with the requirements for Class I installations as found in Appendix J”.


Thus, there is no reason for any concerns regarding so-called inconsistency between classification of hazardous locations in Section 18, and the requirements for suitability of the electrical equipment in such locations.

5.  What is the intent of Rule 18-068?
While conditions under which this Rule is intended to be invoked appear to be quite transparent (see below), the practice has demonstrated that this Rule is misapplied by the CE Code users:

“Rule 18-068 Combustible gas detection (see Appendices B and H)
Electrical equipment suitable for non-hazardous locations shall be permitted to be installed in a Zone 2 location, and electrical equipment suitable for Zone 2 locations shall be permitted to be installed in a Zone 1 location, provided that
  • (a) no specific equipment suitable for the purpose is available;
  • (b) the equipment, during its normal operation, does not produce arcs, sparks, or hot surfaces capable ofnigniting an explosive gas atmosphere; and
  • (c) the location is continuously monitored by a combustible gas detection system that will
    • (i) activate an alarm when the gas concentration reaches 20% of the lower explosive limit;
    • (ii) activate ventilating equipment or other means designed to prevent the concentration of gas from reaching the lower explosive limit when the gas concentration reaches 20% of the lower explosive limit, where such ventilating equipment or other means is provided;
    • (iii) automatically de-energize the electrical equipment being protected when the gas concentration reaches 40% of the lower explosive limit, where the ventilating equipment or other means referred to in Item (ii) is provided;
    • (iv) automatically de-energize the electrical equipment being protected when the gas concentration reaches 20% of the lower explosive limit, where the ventilating equipment or other means referred to in Item (ii) cannot be provided; and
    • (v) automatically de-energize the electrical equipment being protected upon failure of the gas detection instrument”.
Apparently the wording of this Rule has created confusion and inconsistency among the Code users. Many Code users (including inspection authorities) consider that the relaxation allowed under specific conditions of this Rule to the electrical equipment must be also extended to the wiring methods for the referenced equipment; as such approach is logical from the perspective of safety and consistency of electrical installations. These Code users indicate that in many cases, where the existing area classification has to be changed from ordinary location to hazardous location, the existing electrical equipment in the area does not have to be upgraded – to be suitable for the appropriate hazardous location, and could be continued to be used (provided that it meets all conditions listed in this Rule). As well, these Code users are also in the opinion that the relaxation under conditions listed in Rule 18-068 is intended to cover wiring methods to the existing equipment subjected to such relaxation in accordance with this Rule. These Code users indicate that under no condition electrical and fire safety will be compromised if the requirement for use of wiring methods and electrical equipment will be consistent.

If, for instance, the existing equipment in such reclassified area (i.e. in the area that used to be classified as ordinary location, but has to be re-classified as Zone 2 hazardous location) is no longer suitable for this newly established hazardous location, such equipment is permitted to continue to be used in Zone 2 location under all listed conditions of Rule 18-068.

These Code users state that there have been numerous cases, when the existing lighting, ventilation, fire alarm systems and emergency lighting equipment suitable for ordinary location had to operate in the existing industrial facility which was re-classified from a medium hazard industrial occupancy a high hazard industrial occupancy (or from F2 to F1 – from the perspective of the National Building Code of Canada), when let say a boutique distillery moved into the industrial tenant space previously occupied by a small manufacturing tenant, and the already existing equipment and wiring methods to this equipment were not available for Zone 2 hazardous location.

However, these Code users don’t realize that Rule 18-068 was placed into Section 18 (it was numbered differently at the time of its placement into the Code) after a CSA standard for Class I, Division 2 ignition systems was finalized.  At that time most engines were in Class I, Division 1 locations but there wasn’t (and still isn’t) a standard for a Class I, Division 1 ignition system.  There were also many ignition systems that were not approved to the new CSA standard, and as such, Rule 18-068 was intended to allow use of a very specific equipment that was originally suitable for ordinary location only (and which is not available for use in Zone 2 hazardous location) – for installation in Class I, Division 2 locations.  Although, in order to prevent misapplication, the wording of this Rule clearly states that it could be applied where “No specific equipment suitable for the purpose is available”, confusion in this regard still exists, and the proposal has been recently sent to Section 18 S/C – to clarify this Rule. 
 
Hopefully, this follow up article on hazardous locations provides the answers to the questions posted at the outset of the article. However, as usual – the local AHJ must be always consulted for specific issues related to each particular installation. 
EIA Code Article - November 2015
By Ted Simmons 
Ted is the Chief Instructor, Electrical Apprenticeship Program - British Columbia Institute of Technology and is a member of the CSA Part 1 Code Committee. Ted_Simmons@bcit.ca

The 23rd edition of the CEC Part I was introduced to the electrical industry across Canada in January 2015.  The new Code has been extensively updated and contains over 200 revisions.  The changes which are a result of a consensus based process will improve electrical safety, enable Code users to keep pace with emerging technologies, and will provide positive benefits to the entire industry.

It is important to recognize that despite the fact that the 2015 CE Code has been published and is available for purchase, the 2012 CEC will remain in effect until the new Code is adopted by the respective authority having jurisdiction.

In the previous article we provided a brief overview of the most notable changes contained in the 2015 CEC.  In this article we will begin our analysis of each revision and will focus our attention on the changes made to Sections 0 and 2.

Section 0 – Object, scope, and definitions

Approved – This definition has been revised as noted in Subrule (b) to permit the use of other Standards that have been developed by a standards development organization accredited by the Standards Council of Canada, provided the Standards are correlated with provisions of the CEC Part I and do not create duplication with Standards already listed in Appendix “A”.

Energized and energized part – These terms are used in numerous rules throughout the Code and as a result have been defined to ensure consistent application of the requirements.

Receptacle – The terms for receptacle, duplex receptacle, single receptacle, and split receptacle were revised to align with Product Standard requirements.

Motor circuit switch – In order to improve safety for electrical maintenance personnel, this definition has been revised to require that motor-circuit switches whether fused or unfused, rated in horsepower or kilowatts, be capable of interrupting the maximum operating current of a motor of the same horsepower or kilowatt rating as the switch at the rated voltage.

Section 2 – General rules

Rule 2-024 – Use of approved equipment

A new Subrule (2) has been added to clarify the equipment approval requirements for equipment connected on the load side of Class 2 power supplies.  The new Subrule indicates that equipment described in Rule 16-222(1)(a) shall not be required to be approved.

Rule 2-100 – Marking of Equipment

A new note has been added to Appendix “B” to assist Code users with the application of the marking requirements outlined in Rule 2-100(3).  This rule requires that at each distribution point, circuit breakers, switches, etc. be marked in a conspicuous and legible manner to indicate clearly the installation, or portion of installation, they protect and the maximum rating of overcurrent device that is permitted.  

The note explains that the marking required for complex distribution systems, such as systems with multiple sources, should be supplemented with additional information such as single-line diagrams, etc.  The note also indicates this information should be readily available to persons who will operate or work on such systems.

Rule 2-102 – Warning and caution markings

This is a new rule that now requires field installed warning and caution markings, such as those required by Rule 36-006 for High-Voltage installations to be written in the languages mandated by the respective authority having jurisdiction.

Figure 1 shows an example of a warning notice complying with the new marking requirements.


Image courtesy InternationalSafety.com

Rule 2-104 – Electrical equipment ratings

This rule contains two new requirements pertaining to electrical equipment markings.  
Subrule (1) pertains to equipment that is marked with a short-circuit current rating or withstand rating.  These ratings represent the maximum level of short-circuit current that the equipment can safely withstand without suffering damage.

Figure 2 illustrates a typical machine nameplate displaying the SCCR rating.


Image courtesy Eaton

It is critical that the calculated maximum available fault current does not exceed the SCCR or withstand rating marked on the equipment.  As a result, Subrule (1) now requires all electrical equipment marked with a SCCR rating or withstand rating to have ratings sufficient for the voltage employed and for the fault current that is available at the terminals.

Subrule (2) pertains to electrical equipment that is marked with both line-to-line and line-to-ground voltage ratings, such as 125/250V, 600Y/347V, etc.  The new Subrule states that electrical equipment marked in this manner, ie: with a slash voltage rating, shall be permitted to be connected only in a circuit that is solidly grounded.

Items (a) and (b) also require that the nominal voltage of any conductor to ground does not exceed the lower of the two values of the equipment voltage rating, and that the nominal voltage between any two conductors does not exceed the higher value of the electrical equipment voltage rating.

Rules 2-130 and 2-132 – Flame spread requirements

There does not appear to be any changes to either of these rules.  As noted however, in Appendix “B”, there have been significant revisions to the flame spread requirements outlined in the National Building Code of Canada (NBCC) for wiring and cables as well as totally enclosed non-metallic raceways.

The note in Appendix “B” for Rule 2-130 indicates that NBCC Article 3.6.4.3 now requires FT6 rated cables for installation in spaces that may be used as a plenum in buildings of non-combustible construction.

The note in Appendix “B” for Rule 2-132 has also been revised to indicate that NBCC Article 3.1.5.20 requires a FT6 rating for totally enclosed non-metallic raceways when they are installed in a plenum of a building required to be of non-combustible construction.

The notes in Appendix “B” should be consulted for further information on the revised flame spread requirements.

Rule 2-310 – Entrance to, and exit from, working space.

The note in Appendix “B” explaining the requirement outlined in Rule 2-310(1) regarding unobstructed egress to each room containing electrical equipment has been expanded to include information on the NBCC requirements pertaining to the swing of the door.  The note indicates it is intended that doors or gates in the unobstructed means of egress will open in the direction of exit travel.  However, depending on the size of the room with respect to the working space, the NBCC may allow doors or gates located more than 7.6m from the working space to open in either direction.

Further information on this requirement is located in NBCC Articles 3.4.4.4(7), 3.4.3.3, and 9.9.6.1.  

In addition to explaining the requirements related to the direction of travel, Appendix “B” has also been revised to include a note clarifying the intent of Rule 2-310(4).  The note indicates that door hardware of the push-bar type is considered to satisfy the requirement of being readily opened from the equipment side without the use of a key or tool.  The note advises Code users to consult the NBCC Article 3.4.6.16 for further information on this requirement.

Rule 2-324 – Electrical equipment near combustible gas equipment

This rule has been revised and now directs Code users to consult CSA Standard B149.1 regarding the clearance distance required between arc-producing electrical equipment and a combustible gas relief device or vent.  A note has been added to Appendix “B” to indicate that the clearance distances specified in CSA B149.1 are:
    a) 1m for natural gas; and
    b) 3m for propane gas

Rule 2-400 – Enclosures, type designations, and use

There is no change to this Rule, however it should be noted, Table 65 has been expanded to include three new enclosure types: 3X, 3RX, and 3SX.  As noted in the Table, these enclosures provide a degree of protection against corrosion.

In the next article we will begin our review of the changes to Section 4 – Conductors.
Check the EIA website for important updates, events, and news. 

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