Mark C. Ode

Fire/Life Safety Columnist and Code Contributor

Mark C. Ode is a lead engineering associate for Energy & Power Technologies at Underwriters Laboratories Inc. and can be reached at 919.949.2576 and

Articles by Mark C. Ode

July 2015
Safety for solar photovoltaic (PV) systems has come a long way since the first installation requirements were inserted as Article 690 into the 1984 National Electrical Code (NEC). Between the 1984 NEC and the 2014 edition, there have been hundreds of proposals and comments to change the requirements in Article 690, and many of these suggested changes have been implemented into the NEC. READ MORE
June 2015
During the recent 2017 National Electrical Code (NEC) first revision meetings in Hilton Head, S.C., a number of public inputs were submitted to introduce a new cabling system into Article 725 and Article 760. Article 725 covers Class 1, 2 and 3 remote control, signaling and power-limited circuits, and Article 760 covers nonpower-limited and power-limited fire alarm circuits. READ MORE
May 2015
My daughter, Trina Bogart, is an emergency department doctor. She recently emailed me a seemingly simple question. However, when I went to the 2014 National Electrical Code (NEC), I realized it was actually more complicated. The question involved combination toilet and sink units installed in a hospital’s emergency department cubicles, which have receptacles close to the basin. READ MORE
April 2015
The DC Task Group of the NEC Correlating Committee is proposing three new articles for the 2017 edition of the National Electrical Code (NEC). The first is Article 706, covering energy-storage systems (ESS). The second is Article 710, covering microgrids. The third is Article 712, covering direct current (DC) microgrids. READ MORE
March 2015
Are multiwire branch circuits becoming antiquated for most new installations, or are they still being used in most circuit applications? READ MORE
  • Littelfuse Shock-Block Class C and D GFCI
February 2015
I recently taught a 2014 National Electrical Code (NEC) class at an industrial facility in Fort Wayne, Ind., where an attendee asked about special-purpose ground fault circuit interrupters (GFCIs) with trip levels above the normal 4­–6 milliampere (mA) trip threshold level. I told him that the definition of GFCI in the 2014 NEC only recognizes a Class A device. READ MORE
January 2015
Many of the articles I write for ELECTRICAL CONTRACTOR originate as questions from people who read my columns or attend my workshops. This article is based on a question from an electrical contractor friend who is doing an electrical installation in an extremely large hangar being used for painting aircraft. READ MORE
December 2014
Some photovoltaic (PV) inverter manufacturers have designed and built transformer-less inverters to add to their existing line of transformer-type inverters for installation in the United States. Transformer-less inverters have been popular in Europe for quite some time. READ MORE
November 2014
I recently was asked to review a series of emails from a colleague about equipment requirements for ready access or, as defined in Article 100 and used within text in the National Electrical Code (NEC), as “readily accessible.” This phrase is used to describe the location of circuit breakers, for example, permitting ready access to turn the circuit off during times of emergency, when something mal READ MORE