2007 Code Revision and Interpretation Committee Code Interpretation (Last Updated: December 24, 2007)

In an effort to help the electrical industry make a smooth transition into the new Electrical Code and ensure the continuity in the performance of electrical work, the Department of Buildings will be posting code interpretations on its website. Listed below are new code-related questions and corresponding interpretations by the Code Committee. The users of this list should have available the 2005 edition of the NEC and the associated NYC Amendments to the 2005 NEC, as well as (Local Law 49/06) that went into effect on January 1, 2007.

All interpretations are based on the 1999 NEC and associated NY City amendments.

Whenever there are a few sections referenced, the first one is the "lead section", and the rest are secondary sections. All the secondary sections are referenced with the purpose of offering additional clarifications.

Click a topic, or press the enter key on a topic, to reveal its answer.

Chapter 1: General (Section 110.2 to 110.79)

Section 110.2 & 110.3 - (3/7/2007)

  1. It is common practice in the industry to tap onto busbars of existing switchgear, switchboards or panel boards to provide a feed to the disconnects or to the separately mounted circuit breakers. Is such a modification acceptable, and if so does it affect the UL listing of the equipment?
    See Sections 110.2 and 110.3.

Section 110.26 & 110.34 - (4/11/2007)

  1. Sections 110.26 and 110.34 address the requirements for working clearances for electrical equipment rated 600V and below, and over 600V respectively
      1. Are the cable support boxes supposed to comply with the clearance requirements of tables 110.26(A)(1) and 110.34(A)?

    1. Same as "a" if the box contains a splice
    No. These tables do not apply. Sufficient access and working space shall be provided.

Chapter 2: Wiring and Protection (Code Section 200.1 to 285.25)

Section 210.6(C) & 700.9(D)(1) - (7/11/2007)

    1. We are requesting further clarification of a May 9, 2007 committee interpretation relating to the installation of a new engine-generator set in an existing hospital building. In response to a question regarding the required enclosure, the committee's answer indicated that a dedicated 2-hour fire rated room enclosure is not required. The answer also indicated that the engine-generator may share the same space with other mechanical equipment installed within a 2-hour fire rated mechanical room, as long the engine-generator has its own dedicated space.

      NFPA 99 of 1999 (and 2002), under Onsite Generator Set Work Room or Space states that: "Energy converters shall be located in a separate service room dedicated to the generating equipment, separated from the remainder of the building by fire separations having a minimum 2-hour fire rating…Rooms for such equipment shall not be shared with other equipment or electrical service equipment that is part of the essential electrical systems."

      Please revisit the above response.

      Our interpretation is in accordance with the NYC Electrical Code and with section 12-01 of the Rules of the City of NY. Other jurisdictions apply.

    1. Is it permissible to install 277V lighting fixtures in hospital patient rooms and in other unattended sleeping hospital areas?
      Yes. See section 210.6(C).

  1. In high-rise office buildings, should emergency feeders be installed in a 1-hour fire rated multi-purpose shaft or in a dedicated shaft?
    Emergency feeders must be installed using one of the methods described in section 700.9(D)(1).

Section 210.11(C)(3) & 210.23(A) - (11/7/2007)

  1. We are requesting an interpretation regarding the requirements of sections 210.11(C)(3) and 210.23 (A).

    According to these sections, a 20A branch circuit provided for a single bathroom is permitted to supply either the receptacle outlets alone or the combination of lighting units and receptacle outlets.

    Are both methods of wiring acceptable?
    Yes. See the definitions for "Outlet" and "Receptacle" in Article 100.

Section 210.52(D) - (7/11/2007)

  1. Section 210.52(D) requires that bathrooms of dwelling units have at least one receptacle outlet installed within 3 feet of the outside edge of each basin. Is it permissible to locate such a receptacle over a basin?
    Yes. Note that a GFCI is required.

Section 220.14(M) - (7/11/2007)

  1. The new added section 220.14(M) requires that when calculating the ampacity of the branch circuit to an A/C outlet, a load not less than 1500 VA must be included. Can the demand factors of Table 220.42 be applied towards this load?
    No.

Section 225.10 - (1/10/2007)

  1. The new amendment to Section 225.10 does not include the use of wireways as an option for "wiring on buildings." Can an outdoor rated wireway be used for signal systems like the telephone, data and fiber optic? Refer to 770.12(A) and 830.40(I). Also, Article 800 does not mention any special raceway requirements for "on building" installations.
    Yes.

Section 225.30 - (7/11/2007)

  1. This is a follow up to our original question that we submitted to the committee on April 11, 2007, which was:"A new 17 -story building will be built adjacent to an existing 17 -story building. Each building has its own address and lot number, and both buildings will have the same owner. The new building will communicate with the existing building on 13 floors and on the roof.

    a. Is it permissible for the electrical service from the existing building to serve both the existing and the new building?
    b. Is it permissible for one life-safety generator to serve both building?"

    The committee's response was:
    "a. & b. No. See section 225.30."

    Recently, we were informed by the building owners that it is their intention to add into the Certificate of Occupancy a stipulation that one building will not be sold without the other. The two buildings will have one lobby, one heating plant and one chiller plant.

    Additionally, we have received from Con Edison the electric service layout letter which states that both buildings will be served from a single service, originating in the existing building.

    In light of this additional information, we request that the committee reconsider its original interpretation.

    Can an outdoor rated wireway be used for signal systems like the telephone, data and fiber optic? Refer to 770.12(A) and 830.40(I). Also, Article 800 does not mention any special raceway requirements for "on building" installations.
    Based on the additional information provided, it is acceptable to use one electric service and one life-safety generator for both buildings, provided that the buildings comply with all applicable rules and requirements for establishing a single property. The electrical system must comply with section 225.30.

    However, a letter of no objection from the DOB Borough Commissioner is required, as well as Advisory Board approval.

Section 225.30 & 700.9(D) - (4/11/2007)

    1. A new 17-story building will be built adjacent to an existing 17-story building. Each building has its own address and lot number, and both buildings will have the same owner. The new building will communicate with the existing building on 13 floors and on the roof.
        1. Is it permissible for the electrical service from the existing building to serve both the existing and the new building?

      1. Is it permissible for one life-safety generator to serve both buildings?
      No. See Section 225.30.

  1. A new building will be built on a hospital campus. An existing generator plant that is located in a separate power-plant building on campus will provide life-safety emergency power to the new building. It is proposed that the emergency power feeders be routed from the plant building to the new building through one of the other existing building on campus. Are the emergency power feeders that will be routed through the other existing building on campus required to have a 2-hour fire rating?
    A 1-hour fire rating is required, as per Section 700.9(D). This does not preclude the rules and regulations of other jurisdictions.

Section 230.40 - (7/11/2007)

  1. We are doing a job on a lot that has two one-family buildings, one in the front and the second in the rear. Is it permissible to mount the meters for the two buildings on the front building?
    Yes. See section 230.40. However, Advisory Board approval is required.

Section 230.42 - (2/7/2007)

  1. We are a manufacturer of medium voltage switchgear and we request clarification about bus sizing requirements. Considering that the applicable sections are 230.42 and 230.200, we have always interpreted that the 1000A/sq in. (1200A bus) rule does not apply to 4.16KV or higher switchgears, as long as the gear is built in accordance with the applicable ANSI and Con Ed standards. Is our interpretation correct?
    Section 230.42 applies, as per Section 230.200. All installations above 600V must be submitted to the Advisory Board for approval. Request for special permission may be submitted for consideration.

Section 230.42(A)(1) - (11/7/2007)

  1. The NY City Amendments to the 1999 NEC included a revision to section 230-42(a) which read as follows:

    (a) General. The ampacity of the service entrance conductors before the application of any adjustment or correction factors shall not be less than the sum of the maximum ampere ratings of the service disconnects supplied.

    Was this revision retained in the amendments to the 2005 NEC?
    Yes. The old amendment 230-42(a) is now 230.42(A)(1).

Section 230.72(B) - (1/10/2007)

  1. Paragraph 230.72(B) requires that fire pump and fire alarm disconnects "be installed remote from the one to six service disconnecting means for normal service to minimize the possibility of simultaneous interruption of supply". Is it also required that the emergency-source fire pump and fire alarm disconnects be installed remote from the main emergency distribution equipment?
    No.

Section 230.79(A) - (11/7/2007)

  1. According to section 230.79, the minimum rating of a service disconnect is 60A if there are more than two 2-wire branch circuits and the service is not for a one-family dwelling. We have an application for a City agency that involves the installation of control panels with multiple branch circuits at multiple outdoor locations in the five boroughs. All the control panels will receive electrical service from Con Edison. A number of the panels will be provided with Con Ed meters, and their service disconnects will be rated at 60A or higher. For the rest of the panels, Con Ed will provide power from a nearby utility / light pole without the use of a service meter. They will bill the City based on the rating of the service disconnect. Since the load on these panels is minimal (less than 15A), is it acceptable to install a service disconnect rated at 20A?
    Yes, as per section 230.79(A), when only one circuit is involved.

Section 230.90(A) & 230.42 - (11/7/2007)

  1. We are designing the following installation: A 208V, 3 phase, 4 wire electrical service, with maximum service capacity of 3800A, is provided via 10 sets of 4 x 500KCMIL utility service cables. From the service entrance box, 12 sets of 4 x 500KCMIL cables connect to a 1500KVA, 208V / 4160V step-up transformer. The transformer primary current is 4166A, and the secondary current is 208A. The primary of the transformer is protected by a 6000A main service switch fused at 6000A, while the secondary is protected by a 400A switch fused at 300A. Is this installation code compliant?
    The described installation complies with the Exception of the amended section 230.42. However, this installation does not meet the requirements of section 230.90(A). It should be noted that the transformer secondary protection shall comply with Table 450.3(A). This design should be submitted to the Electrical Advisory Board.

Section 240.20(B)(1) - (6/6/2007)

  1. We are planning to connect a subpanel to an existing 3 wire distribution panel. Should the subpanel be fed by a two-pole circuit breaker or by two single pole circuit breakers?
    A two-pole common trip circuit breaker must be used. See section 240.20(B)(1).

Section 240.24(E) - (3/7/2007)

  1. Can a fused busplug disconnect be housed in a shaft adjacent to an ADA toilet? The disconnect's access hatch would open into the toilet area.
    No. See Section 240.24(E).

Section 250.30(A)(7) - (7/11/2007)

  1. We are seeking a clarification regarding the grounding methods for transformers and other separately derived systems installed in buildings made of reinforced concrete. In such buildings, where no common grounding electrode is provided, would either one of the grounding methods described below be acceptable?
      1. A connection to the steel rebar embedded in concrete, as an acceptable grounding electrode.

    1. A connection to a major condenser water riser, as an acceptable grounding electrode.
    No. See section 250.30(A)(7).

Chapter 3: Wiring Methods and Materials (Code Section 300.1 to 398-104)

Section 300.4(E) - (5/9/2007)

  1. In some existing buildings, the walls are made of terracotta blocks (1/2" cement and 1/8" finish plaster). When installing BX cable in a groove in such a wall, what is the required depth beyond the wall surface?
    See Section 300.4 (E).

Section 358.12(7) - (11/7/2007)

  1. Is it permissible to install EMT under a basement slab and in direct contact with the earth?
    No. See NY City amendment 358.12(7).

Chapter 4: Equipment for General Use (Code Section 400.1 to 490.74)

Section 400.8 - (7/11/2007)

  1. One of our vendors is proposing a new method for wiring motorized window shades in office buildings. A receptacle would be mounted within the accessible ceiling space, which conveys environmental air. A window shade motor would be located below the ceiling and connected to the receptacle by an SJ type cord and a NEMA 5-15 plug. Is this proposed wiring method code compliant?
    No. See sections 400.8(2) and 400.8(5).

Section 400.8 - (9/5/2007)

  1. We are in the process of designing a print shop, where the equipment will sit on a 6 inch raised floor. The equipment will be connected via power cords that run through a hatch opening in the raised floor.Section 400.8 does not allow the installation of power cords through holes in the floor. Is the intent of this section to prohibit the connection of appliances / equipment to outlets mounted under raised floors?
    Yes.

Section 400.8 & 392.3(A) - (12/5/2007)

  1. In a communication closet, an Uninterruptible Power Supply (UPS) unit will be installed to provide 120V, 15A power to communication equipment. Is it permissible to use a 3 conductor flexible cord to connect the UPS unit to the communication equipment located 25 ft away?
    No. See section 400.8 paragraphs (1) & (4), and section 392.3(A).

Chapter 5: Special Occupancies (Code Section 500.1 to 590.7)

Section 590.6 - (2/7/2007)

  1. It is our understanding that the 2007 edition of the Electrical Code requires threaded conduit and weathertight fixtures for sidewalk shed lighting. What is the section that addresses this requirement?
    Amendment to Section 590.6 provides the requirements for sidewalk shed lighting installation.

Chapter 6: Special Equipment (Code Section 600.1 to 695.14)

Section 605.6 - (2/7/2007)

  1. The 2005 NEC has added a requirement that multiwire branch circuits supplying power to wired partitions shall be provided with a means to disconnect simultaneously all ungrounded conductors at the panelboard where the branch circuit originates (Sections 605.6 and 605.7).

    Does this mean that it will no longer be acceptable to supply power to "4-circuit" type furniture systems using 3 circuits from a "normal" panelboard and 1 circuit for an "emergency" or "UPS" panelboard (which is common practice in NYC)?
    See the amended Sections 605.6 and 605.7.

Section 620.51(C) - (9/5/2007)

  1. An existing elevator machine room, with multiple entry doors, is being modernized. The new disconnecting means, that will be connected to the existing feeders, have a location that conforms to section 620.51(C) but not by the entry doors. May the existing locations of the disconnecting means be retained?
    Yes.

Section 645.10 - (7/11/2007)

  1. We are requesting an interpretation of the EPO requirement for a Data Center or a similar environment. Is it acceptable to use the factory supplied terminals to shut down the UPS / HVAC equipment or should the incoming feeder be also disconnected?
    In accordance with section 645.10, all power to Information Technology Equipment and HVAC Equipment must be disconnected. This includes the conductors to the PDU and the UPS located in the room as well as the HVAC equipment dedicated to the room. See also section 645.11.

Section 695.5 - (3/7/2007)

  1. The secondary of a step-down transformer, 4160V to 208V, connected to a co-generation station will serve as the emergency feed to a fire pump. Can the fire pump configuration on the emergency source be provided at the secondary of the transformer, but ahead of the main secondary switch?Yes. See the amended Section 695.5.

Chapter 7: Special Conditions (Code Section 700.1 to 780.7)

Section 700.1 - (2/7/2007)

    1. Article 700 of the NEC allows optional stand-by loads (non-life safety) to be fed from an emergency generator. Are two separate transfer switches required for the emergency and non-emergency loads?
      Yes.

    1. The New York City Electrical Code does not define what the emergency loads are. Is there an official listing of such loads?
      The New York City Building Code lists all the emergency loads. See New York City Electrical Code, amendment 700.1.

  1. Can a non life-safety air handler unit be fed from the emergency bus duct system, which in turn is fed from a life-safety ATS?
    No. A separate transfer switch is required.

Section 760.1 - (3/7/2007)

    1. It appears that the NYC Electrical Code prohibits the installation of various communication systems wiring in Electric Closets. Are Fire Alarm System components (such as terminal blocks, panels and risers) allowed to be installed in Electric Closets?
      Yes. See the amendment to Section 760.1.

  1. We are designing an interior fire alarm system for a regular J-2 home used as a day care center. The fire alarm fuse cut-out will be located on the line side of the main service switch, but after the utility meter which is located outside the building. Considering the location of the meter is it acceptable to place the tap after the meter?
    Placing the tap after the meter is acceptable, when using a by-pass meter. See the amendment to Section 760.1.

Articles: A subdivision of a Chapter, comprised of a certain number of Sections

Article 220 - (1/10/2007)

  1. In an apartment building, each apartment is equipped with heat pumps, and individually metered at the breaker panel.
    Can Section 220.16(C) be applied when calculating the 3 phase, 4 wire common feeder?
    Section 220.16(C) applies to receptacle outlets referred to in Section 220.52(I), and not to hard-wired heat pumps. Feeder sizing calculations shall be in accordance with Parts III and IV of Article 220 as applicable.

    It should be noted that if the filing is done prior to July 1, 2007, the installation can still comply with the 2004 NYC Electrical Code (based on the 2002 NEC). However, if the filing will be done after July 1, 2007, all installations will have to comply with the new 2007 NYC Electrical Code (based on the 2005 NEC).

Article 220.32 - (2/7/2007)

  1. Is the final computed load based on Code permitted demand factors considered a continuous or non-continuous load for determining ratings of feeder protective devices or service equipment? For example, computing loads per Article 220.32 Optional Calculation - Multifamily Dwelling a demand factor of 23% may be applied to determine the feeder or service load. Would that be considered a continuous load?
    The final computed load is considered continuous. Same for the example.

Article 348 - (9/5/2007)

  1. Can flexible metal conduit (Greenfield) be used as an alternative wiring method to replace conduit in a 15 story riser?
    Yes, as permitted by Article 348.

Article 517 & 700.9 - (11/7/2007)

  1. Section 517.41(E) requires that "the cover plates for the electrical receptacles or the electrical receptacles themselves supplied from the emergency system shall have a distinctive color or marking so as to be readily identifiable."
      1. Under Article 517, can we still use the color red to be code compliant?
        Yes.

    1. Does section 700.9 require the use of the color yellow for the emergency receptacles?
      No.

Article 555 - (3/7/2007)

  1. We are in the process of repairing the wiring on the Bulkhead and Docks of a private Yacht Club, where the existing PVC conduit was cut off when the docks were rebuilt. Is it permissible to install new junction boxes on the remaining PVC conduits and extend the wiring to re-feed the panels by using new PVC conduit?
    Yes. See Article 555.

Article 720 - (5/9/2007)

  1. We are planning to install a new 277/480V generator, as an optional power source to back-up an existing life safety generator that serves a distribution board feeding transfer switches that are properly dedicated to emergency loads, in accordance with article 700.6(D). We intend to use a new generator-to-generator transfer switch ahead of the distribution board, intercepting the existing feeder from the existing generator to the distribution board. This ATS will transfer to the optional generator only upon the failure of the existing emergency generator.
    The new generator shall be installed in accordance with Article 702, assuming that the existing life safety requirements are in compliance with the code.
      1. The new transfer switch that will not be connected to the normal source will ultimately feed a combination of life safety and optional loads. Does this violate section 700.6(D)?
        No.

      1. Since t could serve life safety loads, is the new generator prohibited from having ground fault protection?
        Since this is an optional stand-by generator, ground fault protection is required, as per Article 702.

      1. Connect the new generator, to the new transfer switch and to the existing distribution board?
        No.

    1. If the answer to Question c. is yes, would we need to retroactively modify the existing wiring from the existing generator to the new transfer switch to comply with this section?
      N/A.

Administrative: General Requirements

    1. The Board of an existing 40-story apartment building, classified as Occupancy Group J-2, would like to install a backup generator and automatic transfer switches to provide power to two elevators, the lobby lighting, corridor and stairway lighting. To the best of our knowledge, the NYC Building Code did not require emergency power when the building was constructed and there are no outstanding violations regarding emergency power.
        1. Since the generator and the automatic transfer switches are being installed voluntarily, can they be classified as an Optional Standby System under Article 702 of the Electrical Code?

        1. The Fine Print Note No. 3 of section 700.1 reads in part that "Emergency systems are...legally required...". Since this generator is being installed voluntarily and is not legally required, can we assume that this generator would NOT be classified as an emergency generator?

        1. If the answer to (b) is YES, then can we also assume that sub-section 700.12(B)(2) requiring an on-site fuel supply would NOT apply to this installation?

      1. Can the generator, as described above, have a utility-supplied natural gas fuel source? (12/5/07)
      See DOB's Technical Policy & Procedure Notice (TPPN) 1/07

    1. We are designing a new EMS building which will be operated by the Fire Department. The building will have a basement and two floors, each with a gross area of 10,000 square feet. The building will be classified as a Type E occupancy. The normal electrical service will terminate at the metering and main switch located in the basement. There will be an emergency generator in the building, as per the FDNY requirements, which we located on the first (ground) floor. Both the emergency lighting and the smoke detection system will be connected to the generator. The FDNY is now directing the location of the generator and of the automatic transfer switch (ATS) into the basement, which is the lowest level of the building and the level of the normal service.

      Our firm has referenced the NYC Electrical Code section 700.9(C) citing adverse location.
        1. Is this generator legally required for this building?

        1. If this generator is voluntary, does it have to be installed per code, as though it is legally required?

        1. Are there any situations where the transfer switch and / or generator can be located on the lowest level, subject to adverse conditions?

        1. Can we locate the generator and / or the ATS in the basement of this building without violating codes?

        1. If If the generator and the ATS are located in the basement, on the same level as the normal service, is the generator and ATS considered only a standby system?

      1. Same Same as question (e), is the generator and the ATS considered an emergency system? (12/5/07)
      This is a Building Code (BC) issue for which the Committee is not charged with interpreting. However, please see section 27-396.6 of the BC and DOB's Technical Policy & Procedure Notice (TPPN) # 1/07.

    1. We would like to verify the calculation method for determining a residential service load, when motorized window shades are included. The shade motors are often 120V, 2A each, and fixed in place. They operate only when the position of the shades is changed. Are they considered:
        1. Part of the general lighting and receptacle load, and therefore included in the 3 watts per square foot lighting allowance.

        1. A fixed in place appliance, and included per 220.53.

      1. A motor load, and included per 430.24.
      If none of the above, how should they be considered? (11/7/07)
      Motorized window shades are considered to be "part of the general lighting and receptacle load - a."

    1. Can a one-family house have a second meter dedicated to the public lighting panel (PLP)?
      No.

    1. If a homeowner changes his certificate of occupancy from a two-family to a one-family is he or she required to remove all but one meter?
      See section 27-3021.1 of the Administrative portion of the Code.

    1. Can an absentee homeowner of a one-family house apply for an additional meter? (9/5/07)
      No.

    1. Is Advisory Board approval required for PV systems that are installed by a NYC licensed electrician, are tested and listed by a nationally recognized testing laboratory (NRTL), and for which a registered professional files a PW -1 form with the DOB? (9/5/07)
      No.

    1. We are designing an individually coded fire alarm system for a commercial space located on the ground floor of a multi-story residential building. This system will be connected to the building fire alarm system. Due to the cramped conditions within the main electrical room, it is impossible to install the fuse cut-out for the fire alarm system ahead of the main service switch. As a result, we are proposing the following design:

      Power for the tenant Fire Alarm Control Panel (FACP) will be obtained from a fuse cut-out tapped ahead of the distribution panel within the tenant space or from a branch circuit panel, instead of the building main service switch. The tenant FACP will be provided with batteries that can last for 24 hrs in supervisory mode and 60 min. in alarm mode after a loss of power. In addition, the tenant FACP will be connected to a central monitoring station.

      Is this design acceptable? (9/5/07)
      Yes, subject to the requirements of RS 17-3 of the Building Code. Also, verify acceptance with the NYC Fire Department.

    1. Is it permissible to install service entrance conductors for fire pumps in a 2-hour fire rated service room without encasing the conduits in concrete? (7/11/07)
      Yes.

    1. Telecom Equipment. Is it permissible to install telecommunication equipment in a closet with electrical conduits rising vertically? A 1-inch thick plywood will separate the conduits from the telecom equipment.
      No.

    1. Telecom Equipment Risers. Is it permissible to install vertical cable risers for telecom equipment in an electrical meter bank closet exposed without conduits?
      No.

    1. Kitchen Cabinets
        1. Is a kitchen base-cabinet, that separates the kitchen from the living room, considered to be a wall space?
          Yes.

        1. The kitchen base-cabinet measures approx. 9 feet in length. Can a convenience receptacle be installed on an adjacent wall, on the living room side, extending the 6 foot rule of 210.52(A)(1)?
          No.

      1. Same Same question as c.2., except that the kitchen base-cabinet measures 7½ feet. (6/6/07)
        No.

    1. We are working on the electrical design for a new 6 story apartment building. In terms of metering, our client is requesting one master meter at the incoming service and separate sub-meters for every apartment. Is it permissible to use sub-metering in apartment buildings? (5/9/07)
      The sub-metering issue is not addressed in the NY City Electrical Code. It is the committee's opinion that the use of sub-metering in an apartment building is acceptable. However, it is subject to the utility's approval as well as other city and state agencies whose approval may be required as part of the specific projects.

    1. We are designing the emergency power system for an existing building. Our design includes a 480 V generator, a 480 - 120/208 V delta / wye transformer and a 3 pole ATS. Is the use of a 3 pole ATS code complaint? (5/9/07)
      Where transformers are used as a non-separately derived system, this design does not violate the code. However, it is recommended that a redundant equipment grounding conductor, that would bond the transformer enclosure and the ATS enclosure to the service ground, be used. The equipment grounding conductor shall be properly sized in order to minimize the effects of the ground fault currents during generator operation.

    1. With regard to DOB's Rule 1 RCNY 12 - 01, we are requesting the following clarification:
        1. When nstalling a new engine-generator in an existing hospital building, is a dedicated 2- hour fire rated room enclosure required?
          No.

      1. Can the engine generator share the same space with other mechanical equipment installed within a 2-hour fire rated mechanical room? (5/9/07)
        Yes, as long as the engine-generator has its own dedicated space within the common room.

    1. Is it permissible to install telecommunication/data equipment in the same room as a single 208V distribution panel? All working clearances will be adhered to and no substantial electrical distribution equipment will be installed in the room. (5/9/07)
      Yes. The described room does not meet the definition of an electrical closet.

    1. The testing of switchgear relays is usually performed in accordance with the National Electrical Testing Association's (NETA) procedures. The relays are first disconnected from the switchgear and then placed on a test bench where they are visually inspected, tested and calibrated. After they are re-certified, the relays get re-connected to the switchgear. Is this type of work required to be performed only by a licensed electrician? (4/11/07)
      The inspection, testing, and calibration of relays are not covered in the Electrical Code. However, the committee is providing the following comment. The bench testing of the relays is not relevant to an electrician's work. The only operation for which an electrician is required, is the removal and the re-connection of the relays from and to the switchgear.

    1. We are a telephone company and our field installations include an Optical Network Equipment Cabinet that contains an AC/DC power supply. Is it permissible to install such a cabinet recessed into the wall of a regular closet? (4/11/07)
      Yes, if listed for the purpose.

    1. Many office spaces use movable equipment counters and conference room tables that need power and data connections.
        1. Can a receptacle outlet with a cord and plug connection be field assembled at these locations and plugged into an adjacent receptacle on the wall or floor?
          No.

        1. Same as in Question "a", if not field assembled, but pre-assembled and listed for the purpose (relocatable power taps)?
          Yes.

        1. Can there be more than one duplex receptacle installed in the common assembly?
          Yes.

        1. As in Question "c", can the receptacles be hardwired with an approved flexible raceway?
          No.

      1. Since this is not a residential kitchen, can the receptacle be surface mounted (not flush) in a box with the receptacles facing up? (3/7/07)
        No.

    1. It is our understanding that the wiring for the line voltage side of a lighting control system must be installed by a licensed electrician. Please clarify if the wiring for the low voltage side of such a system must also be installed by a licensed electrician. Should such clarification be added into the code? (3/7/07)
      Such clarification already exists in the current NYC Electrical Code. See the definition for Low Voltage Electrical Work, Section 27-3004 of the Administrative Portion.

    1. The code clearly indicates that only the wiring directly associated with the operation of an elevator or a dumbwaiter is permitted to be installed in the hoistway. Can regular wiring be installed in a permanently abandoned dumbwaiter hoistway, or is special permission required? (3/7/07)
      Yes. The hoistway must first be decommissioned in accordance with DOB rules. Cables and raceways must be properly supported. No special permission is required.

    1. It is our understanding that for an IT room designed to comply with Chapters 1 through 4, the use of an Emergency Power Off (EPO) station is not required. When Article 645 is used as an alternate design approach, the use of an EPO is also required. Is our interpretation correct? (2/7/07)
      Yes.

    1. Can 24V DC wiring for LED lighting be routed within PVC conduit in external buried locations or on roof-top pedestrian park structure where concealed in concrete? (2/7/07)
      Yes.

    1. Is it permissible to install a light switch inside a walk-in clothes closet? (2/7/07)
      The code does not prohibit the installation of a light switch inside the closet.

  1. It is common in New York City that property owners have to upgrade their water service. In such situations, the plumbing contractor never re-installs correctly the water pipe ground or the jumper over the water meter. Who has the responsibility for reconnecting the ground wire? (2/7/07)
    It is the owner's responsibility to have the ground wire reconnected.

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