Mark C. Ode

Fire/Life Safety Columnist and Code Contributor

Mark C. Ode is a staff engineering associate at Underwriters Laboratories Inc., based in Peoria, Ariz. He can be reached at 919.949.2576 and

Articles by Mark C. Ode

October 2009
The 20th and 21st centuries have seen many changes in gasoline stations. READ MORE
September 2009
The purpose of ground-fault protection on temporary wiring installations during construction, remodeling, maintenance, repair or demolition of buildings, structures or equipment is to ensure personnel protection. Section 590.6 re-quires ground-fault circuit interrupter (GFCI) protection for any temporary power source supplying electrical equipment on the job site. READ MORE
August 2009
In section 250.52(A)(2) of the 2005 and the 2008 editions of the National Electrical Code (NEC), the metal frame of a building or structure is considered to be a grounding electrode if the metal frame is connected to earth by one of four different methods. Upon analyzing the four different methods, many electricians’ question whether the four methods provide an appropriate connection to earth. READ MORE
July 2009
Recently, I fielded a question about the basic statement in Section 695.3 of the 2008 National Electrical Code (NEC) that “electric motor-driven fire pumps shall have a reliable source of power.” The question involved the reliability of the power source for one of the most important electrical motors in a building. READ MORE
May 2009
While preparing a presentation, I noticed a photo taken at a facility where temporary power was needed periodically. The facility rented a generator when necessary. It showed a disconnecting means with four individual conductors stubbed out of the bottom of the enclosure. READ MORE
March 2009
Many are aware that electrical equipment arcing and sparking -can cause chemical atmospheres (gases, vapors and dusts) to ignite. However, we often forget that thermal ignition of these chemical atmospheres also can occur if the chemicals are exposed to high temperatures. READ MORE
February 2009
A requirement for short-circuit current rating was added in the 2005 National Electrical Code (NEC) to Section 430.8 covering motor controller marking, to Section 440.4(B) covering controller marking for air conditioning and refrigerating equipment, and to 409.110 covering controller marking for industrial control panels. READ MORE
November 2008
Emergency circuits are installed in patient bed locations in general care and critical care areas in hospitals to ensure power is available to electrical equipment even where normal power is lost for some reason. READ MORE
October 2008
Many installations have exposed raceways and electrical equipment of all kinds on rooftops, walls and other direct sunlight applications, since this has been a common installation method for many years. READ MORE