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.
 Previous use of gray conductors

Article 310 in the National Electrical Code (NEC) covers general requirements for conductors and their type designations, insulations, markings, mechanical strengths, ampacity ratings and uses.

A recent change in the 2014 National Electrical Code (NEC) creates a new method for determining the size of service and feeder conductors for 120/240-volt (V), single-phase services for one-family, individual units of two-family dwellings, and individual units for multifamily dwellings.

The 2014 National Electrical Code (NEC) has new requirements for field-applied hazard warning markings, signs and labels. Throughout the NEC, rules that required signs, labels and other markings also required a specific signal word be included in the sign, label or marking.

More on Codes & Standards

Digging Into The Past

Many of the articles that I write for this magazine originate as questions that I receive as I travel, by phone, or come to me as emails. I can answer some of these questions very easily without much controversy by a simple reference to the National Electrical Code (NEC).

Sizing Conductors, Part XXV

As a general rule in the National Electrical Code (NEC), the ampere rating of the overcurrent device (fuse or breaker) must not be less than the ampacity of the conductor.

Seal The Deal

Requirements for electrical wiring in hazardous (classified) locations are more restrictive than in the rules for wiring in general types of occupancies.

Connecting The Grounding Electrode Conductor, Protecting Copper And More

If you have a problem related to the National Electrical Code (NEC), are experiencing difficulty in understanding a Code requirement, or are wondering why or if such a requirement exists, ask Charlie, and he will let the Code decide. Questions can be sent to

The Best Is Yet To Come! IEEE 1584 Update

A lot has happened since 2002 when IEEE 1584–IEEE Guide for Arc-Flash Hazard Calculations was first published by the Institute of Electrical and Electronics Engineers.

In The Drink

In the 2011 and previous editions of the National Electrical Code (NEC), installing low-voltage lighting in close proximity to the edge of a swimming pool was a Code violation, yet almost every backyard swimming pool with a landscaped yard has low-voltage lighting too close to the pool’s edge.

Sizing Conductors, Part XXIV

The overcurrent device rating is a key factor when determining the correct size conductor. Article 240 in the National Electrical Code (NEC) provides general requirements for overcurrent protection and overcurrent protective devices.