NFPA 70E Research Articles

IR sightglasses protect against arc-flash exposure

The intense energy and duration of an electric arc flash represents a very unique exposure. Everyday work clothes made from regular cotton or polyester cotton blended fabrics, regardless of weight, can be readily ignited at some exposure level. Once ignited, the clothing will continue to burn, adding to the extent of the injury sustained from the arc alone. The National Fire Protection Association (NFPA 70E) standard for electrical safety requirements for employee workplaces now requires employees to wear flame-resistant (FR) protective clothing wherever there is possible exposure to an electric arc flash. This clothing must meet the requirements of ASTM International, formally known as the American Society for Testingand Materials (ASTM) document reference F1506. It also requires employers to perform a flash hazard analysis to determine the flash protection boundary distance.

Electrical hazard analysis

The subject of electrical hazard analysis has been recognized by a small segment of the electrical industry for many years. The petrochemical industry and many government institutions have performed research on this subject for over 20 years. For the most part, however, the electrical industry - at least at the user level - has largely ignored the subject. Essentially, the industry has reacted to catastrophic accidents, rather than proactively trying to predict and prevent them. Recent changes in consensus standards, along with a better general understanding of the seriousness of electrical hazards, have resulted in a renewal of interest in the subject. This article addresses the requirements for performing the shock hazard analysis and flash hazard analysis required by NFPA 70E, Section 110.8(B)(1), Electrical Hazard Analysis, as well as the blast hazard analysis and personal protective equipment (PPE) requirements.

Refocusing Electrical Safety

Electrical safety needs to be refocused. Over the last few years, there has been tremendous attention given to the arc flash hazard phenomenon. Even though this hazard needs attention to reduce the number of injuries occurring because of it, in some ways, it has become the predominate focus of electrical safety. Electrical safety is more than just the arc flash hazard. Electrical safety needs to be a holistic approach that includes all aspects of electrical safety. The Electrical Safety Program, which proved to be a good tool, is defined in NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces. However, even this falls short of what is needed to make a step change in electrical safety performance. This paper will attempt to identify the voids in electrical safety and focus attention on the items that need to be addressed to take a more holistic approach to electrical safety

NFPA 70E

National Fire Protection Association 70E, standard for electrical safety in the workplace is a consensus standard approved as an American national standard. Whereas the NFPA 70 National Electrical Code is primarily an installation standard for premise electrical systems, focuses on electrical safety requirements to protect individuals working on or near electrical equipment. This article will discuss some of the key aspects of the 2004 Edition of NFPA 70E, with a focus on safety-related work practices. In addition, this article also presents some of the potential directions for requirements in future editions of NFPA 70E.

Arc flash calculations in systems protected by low-voltage circuit breakers

A series of previous papers has provided information regarding the arc flash hazard and methods of calculating its potential impact on persons working on or near the equipment. This paper extends that base of information by focusing on the arcing current level and duration in low-voltage circuits protected by circuit breakers (CBs). It describes a method of calculating incident energy and the flash protection boundary due to arcing occurrences in equipment protected by CBs. This method provides convenient procedures for determining these values for generic situations in which some details of the CB are not known. Further, it provides a process for determining these values in typical feeder and branch circuit applications involving common transformers and cable sizes and lengths. The values are needed to determine safe work practices and appropriate Personal Protective Equipment to comply with NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces.

NFPA 70E 2000: updating electrical safety requirements for employee workplaces

The authors describe NFPA 70E, which is intended primarily for those who commission, start up, operate and maintain electrical systems and equipment. Safe condition of electrical facilities and equipment is best achieved by adherence to NFPA 70, the National Electrical Code, during the design, procurement, and installation phases of such equipment. Following the policies, principles, practices and procedures advocated by NEPA, 70E provides a reasonable and effective approach to the safe conduct of electrical work by employees in the workplace.

Implementing electrical safety regulations and standards

Since the creation of OSHA in 1912, there have been continuing changes in regulations, codes and standards impacting work practices and exposure to hazardous electrical energy. These include, but are not limited to, various OSHA regulations, NFPA 70E (1988 & 1995), National Electrical Code and National Electrical Safety Code. These consensus documents are written with the intention to establish lower injury performance expectations, or to offer guidance in developing work practices that lower the risk of personnel injury. In order to have an impact in the workplace, people in the workplace must transform often general or generic expectations or guidance into changes in specific practices that may be unique for their industry, plant or work environment. A successful and effective transformation process typically requires participation and support from management, technology experts, safety professionals, and the work force (whom the changes are intended to protect). This article provides insight in the transformation process used successfully in several companies. While the details may vary from company to company, as well as from different plants within each company, the elements for success are viewed as common.

Safety practices in electrolytic cell line working zones: 1994 changes

In 1974 the Electrical Cell Line Working Group of the Chemical Industry Committee prepared a trial-use standard for Electrical Safety Practices in Electrolytic Cell Line Working Zones. Comments on the trial-use standard were incorporated into a full-status standard and published as IEEE Std 463-1977, IEEE Standard for Electrical Safety Practices in Electrolytic Cell Line Working Zones. IEEE Std 463-1977 was reaffirmed in 1987. IEEE Std 463 was used as a source document for Article 668, Electrolytic Cells, of the National Electrical Code (ANSI/NFPA 70); Part 1, Chapter 4H, Specific Purpose Equipment and Installations-Electrolytic Cells of the Standard for Electrical Safety Requirements for Employee Work Places (NFPA 70B-1988); and OSHA 1910.306(h), Electrolytic Cells. In 1991 a working group was formed to review and update IEEE Std 463. The purpose of this article is to describe the current update to IEEE Std 463. The current application of IEEE Std 463 in relation to NFPA 70; NFPA 70E, Parts 1 and 2; and OSHA 1910 Subpart S-Electrical are discussed.

Effecting changes in the National Electrical Code

The complete revision cycle for effecting changes in the National Electrical Code (NEC) is defined. Procedures for submitting proposals to revise the NEC are addressed. The same procedures can be applied to other documents sponsored and issued by technical committees of the National Fire Protection Association such as NFPA 78, Lightning Protection, and NFPA 70E, Electrical Safety Requirements for Employee Workplaces.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>