Michael Johnston

Article 100 is the keeper of national electrical code definitions. The NEC Style Manual indicates that if a word or term is used in more than two articles, then it should have a definition in Article 100. Article 100 of the...

Communications systems and equipment installed in buildings must comply with the specific rules given in Chapter 8 of the NEC . Even though these systems typically operate at lower energy levels, improper grounding and...

If circuits are intrinsically safe (IS), the energy is at a low enough level that ignition of an explosive atmosphere will not occur if the circuit is opened, shorted or faulted to ground at the same time a fault occurs at...

The National Electrical Code Section 700.10(A) requires all boxes and enclosures­—including transfer switches, generators and power panels that are part of an emergency system—to be marked so they are readily identifiable as...

The National Electrical Code has several requirements applicable to emergency systems, legally required standby systems, essential electrical systems and optional standby systems. From a basic performance standpoint, the...

People are fallible and human error often causes accidents, so assessing worker performance is an important part of maintaining a safe work environment. Incidents can be avoided by understanding what contributes to human...

In 1996, when the National Electrical Contractors Association was developing National Electrical Installation Standards (NEIS) for the electrical construction industry, the initial effort included the development of NECA 1...

Recently, I was asked to explain the reason for the ferrous metal raceway bonding requirements in 250.64(E). Although the National Electrical Code never uses the term “choke effect,” many in the business understand its...

To understand the purpose of ground-detection equipment installed for ungrounded systems, it is best to have a fundamental understanding of ungrounded system performance and the rules that apply to them. Section 250.4(B)...

COVID-19 continues to test safety and health management systems on every level. While many organizations scrambled to develop or shore up their safety practices to deal with the pandemic, others saw it as business as usual...