Codes & Standards


Essential to the work of the electrical contractor is knowledge of the National Electrical Code, the National Electrical Installation Standards and additional standards and codes administered by the National Fire Protection Association, the Occupational Safety and Health Administration and others. Here is a list of all our articles on codes and standards listed chronologically by issue date. 

Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC), Jim will help you solve it. Questions can be sent to Answers are based on the 2014 NEC.
 Arc-resistant switchgear

For my December 2005 column in ELECTRICAL CONTRACTOR, I wrote about the installation of parallel conductors in a metal wireway and the subsequent heating effects. These heating effects occur whether the parallel conductors are installed in a metal or nonmetallic wireway or in an auxiliary gutter.

Article 110 in the National Electrical Code (NEC) covers general requirements for the examination and approval, installation and use, access to and spaces about electrical conductors and equipment; enclosures intended for personnel entry; and tunnel installations [110.1].

Special rules for ground-fault protection of equipment (GFPE) apply to healthcare facilities. Section 517.17(A) indicates that these GFPE rules apply to hospitals and other buildings (including multiple occupancy buildings) with critical-care space or where life-support equipment is used.

More on Codes & Standards

Overcurrent Protection, Disconnecting Means and Mo

Disconnecting means Q: Disconnecting means for circuits supplied by a generator are required where the circuits enter a building or structure. Are these disconnects from an outdoor generator required to meet the rules in Article 225? Is there a maximum number of disconnects permitted?

Branch-Circuit, Feeder and Service Calculations, Part III

220.14 Other Loads—All Occupancies Article 220 of the National Electrical Code (NEC) contains requirements for calculating branch-circuit, feeder and service loads. Knowing how to perform load calculations is an essential part of being an electrician.

Entries into Raintight Enclosures, Derating NM-B C

Cables in metal framing member Q: Sections 320.17 and 330.17 require that Types AC and MC cables be installed to comply with 300.4.

Branch-Circuit, Feeder and Service Calculations, Part II

An essential part in the life of an electrician is performing load calculations. Determining what size conductors and overcurrent protective devices to install is something most electricians do on a daily basis.

Household Applications and the Code

Providing branch-circuit overcurrent protection and subdividing electrical resistance-heating elements in appliances and fixed electric space heating equipment has been a long- standing requirement in the National Electrical Code (NEC).

Assembly Occupancies, Overcurrent Protection and More

Electric service for grounding-electrode conductors Q: The electric utility in our area requires the installation of a ground rod and grounding-electrode conductor in the meter socket. Is it acceptable to ground the grounded-circuit conductor (neutral) in the service-disconnect enclosure?

Branch-Circuit, Feeder and Service Calculations
by Staff |

220.1 Scope Understanding how to perform load calculations is an important part of an electrician’s professional career. Before obtaining a permit, some jurisdictions require paperwork showing load calculations for services and feeders.