AFCI Requirements Page 1 of 3 Revision Date: 01/15/2019

City of Palo Alto Development Services Building Division – 285 Hamilton Av. (First Floor), Palo Alto, CA 94301 – (650) 329-2496

DEVELOPMENT SERVICES – BUILDING INSPECTION

INSPECTION GUIDELINES: ARC-FAULT CIRCUIT INTERRUPTER (AFCI) REQUIREMENTS

INSPECTION CODE: 220, 246, 407, 101

SCOPE: RESIDENTIAL

CODES ENFORCED: 2016 CBC, CRC, CPC, CMC, CEC, CALGreen, CEnC, and PAMC

The information provided in this document is general and intended as a guide only. Each project is unique and additional requirements may be enforced as deemed appropriate.

BACKGROUND Arc-fault circuit interrupters (AFCIs) Most people are familiar with the term “arcing.” Arcing may be intended, such as with an arc welder, or unintended, such as when a tree falls on a power line during a storm creating a current discharge between conductors or to the earth. An arc fault is an unintended arc created by current flowing through an unplanned path. Arcing creates high intensity heating at the point of the arc resulting in burning particles that may easily ignite surrounding material, such as wood framing or insulation. A series arc occurs in electrical wiring when there is a small gap or break in a conductor. A parallel arc occurs when a small gap or break which permits current to flow to ground (a ground fault) or between the hot and neutral wires (a short circuit). An arc-fault circuit interrupter (AFCI) is a product that is designed to detect a wide range of arcing electrical faults (including series and parallel) to help reduce the electrical system from being an ignition source of a fire. Conventional overcurrent protective devices do not detect low level hazardous arcing currents that have the potential to initiate electrical fires. The objective is to protect the circuit in a manner that will reduce its chances of being a source of an electrical fire. CALIFORNIA ELECTRICAL CODE CEC 210.12(A) states that “all 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms, sunrooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, and sunrooms, recreation rooms, closets, hallways, laundry areas, or similar rooms or area shall be protected by any of the means described in 210.12(A)(1) through (6).” NOTE: “Outlets” include receptacles, lighting, other outlets, and other points of use. SOURCES

https://www.afcisafety.org/afci/what-is-afci/#1469599930228-af1035c1-803f

https://inspectapedia.com/electric/Arc_Fault_Circuit_Breaker_Interruptors_AFCI.php

https://iaeimagazine.org/magazine/2015/05/22/whats-new-about-afcis-in-the-2014-nec/

http://www.cooperindustries.com/content/dam/public/wiringdevices/products/documents/brochures2/afci-educational-take-one.pdf

AFCI Requirements Page 2 of 3 Revision Date: 01/15/2019

City of Palo Alto Development Services Building Division – 285 Hamilton Av. (First Floor), Palo Alto, CA 94301 – (650) 329-2496

INSPECTION ROUGH-IN The installer shall inform the inspector at the time of rough-in inspection which option will be used to

meet the AFCI requirements. The steps in the rough-in inspection will change depending on the option to be installed (see the table in the page that follows).

o Exception: Where an individual branch circuit to a fire alarm system installed in accordance with CEC 760.41(B) or CEC760.121(B) is installed in RMC, IMC, EMT, or steel sheathed cable, Type AC or Type MC, meeting the requirements of 250.118, with metal outlet and junction boxes, AFCI protection shall be permitted to be omitted.

For extensions or modifications, the branch circuit can only be protected using means (1) or (2). (CEC

210.12(B)) o EXCEPTION: AFCI protection is not required if the extension of the existing conductors does not

exceed 6 ft. and does not include any additional outlets or devices. ELECTRICAL TORQUE/HOT CHECK & FINAL See the table in the page that follows for requirements. The images below are examples for methods

(1) and (2).

Combination-type AFCI circuit breaker (CEC 210.12(A)(1))

Branch/feeder-type AFCI circuit breaker + outlet branch circuit (OBC)-type AFCI receptacle (CEC 210.12(A)(2))

AFCI Requirements Page 3 of 3 Revision Date: 01/15/2019

City of Palo Alto Development Services Building Division – 285 Hamilton Av. (First Floor), Palo Alto, CA 94301 – (650) 329-2496

AFCI Protection Method Rough-In Inspection Electrical Torque/Hot Check/Final Inspection

1. Combination-type AFCI circuit breaker (CEC 210.12(A)(1))

Verify all wiring from the source of the branch circuit. Verify that the breaker has “combination” on the label

Witness torque of breaker, including connection to the neutral bar

Perform hot check on all receptacles

2. Branch/feeder-type AFCI circuit breaker + outlet branch circuit (OBC)-type AFCI receptacle (CEC 210.12(A)(2))

Verify that the outlet box in the branch circuit is marked and will be readily accessible.

Verify that the first outlet is marked to indicate that it is the first outlet of the branch circuit

Witness torque of breaker, including connection to neutral bar

Perform hot check on all receptacles

3. Supplemental arc protection circuit breaker + OBC-type AFCI receptacle (CEC 210.12(A)(3)) *

Provide documentation for supplemental arc-protection circuit breaker as there are currently no supplemental arc-protection circuit breakers on the market.

Verify that the branch circuit wiring is continuous.

The home run may not exceed 50 ft for 14 AWG and 70 ft for 12 AWG conductors.

The OBC AFCI located in the first outlet box in the branch circuit.

Verify the documentation for the supplemental arc-protection circuit breaker

Verify that the first outlet is marked to indicate that it is the first outlet of the branch circuit

Witness torque of breaker, including connection to neutral bar

Perform hot check on all receptacles

4. System combination-type AFCI (CEC 210.12(A)(4)) *

If using this option, the contractor shall provide documentation for system combination-type AFCI as there are currently no tested combinations of AFCI receptacles and breakers on the market.

Verify that the branch circuit wiring is continuous.

The home run may not exceed 50 ft for 14 AWG and 70 ft for 12 AWG conductors.

The OBC AFCI located in the first outlet box in the branch circuit.

Verify the documentation for the system combination-type AFCI

Verify that the first outlet is marked to indicate that it is the first outlet of the branch circuit

Witness torque of breaker, including connection to neutral bar

Perform hot check on all receptacles

5. OBC-type AFCI receptacle + steel wiring method (CEC 210.12(A)(5))

Verify that RMC, IMC, EMT, Type MC, or steel-armored type AC cables, metal wireways, metal auxiliary gutters, and metal outlet and junction boxes are installed. The branch circuit wiring must be continuous.

Verify that the outlet box in the branch circuit is marked and will be readily accessible.

Witness torque of conduit grounding at branch source and of breaker

Verify that the first outlet is marked to indicate that it is the first outlet of the circuit

Perform hot check on all receptacles

6. OBC-type AFCI receptacle + concrete encasement (CEC 210.12(A)(6))

Verify that metal or nonmetallic conduit/tubing or Type MC cables are encased in not less than 2” of concrete. The branch circuit wiring must be continuous.

Verify that the outlet box in the branch circuit is marked and will be readily accessible.

Witness torque of conduit grounding at branch source and of breaker

Verify that the first outlet is marked to indicate that it is the first outlet of the circuit

Perform hot check on all receptacles

* Methods (3) and (4) may not be available in the market and you may have to use methods (1), (2), (5), or (6).