February 21, 2024

Historical Timeline of NFPA 70B

This timeline displays the development of the latest standard over several decades and an overview of the topics and practices included in the code.


This timeline displays the development of the latest standard over several decades and an overview of the topics and practices included in the code.

In January 2023, the National Fire Protection Agency (NFPA) updated the standard for Electrical Equipment Maintenance, NFPA 70B. This standard and NFPA 70 (National Electric Code) and NFPA 70E (Standard for Electrical Safety in the Workplace) have been longstanding recommendations. Here’s a chronological overview of the development of NFPA 70B, showcasing its evolution over several decades and an outline of the topics.

1967 — An ad hoc committee on electrical equipment maintenance was authorized by NFPA. While there were suggestions to include maintenance recommendations in the National Electric Code (NEC), it was determined that the NEC was not the appropriate place. NFPA was responsible for assessing the need to develop a formal document.

June 27, 1968 — NFPA established the Committee on Electrical Equipment Maintenance to develop texts related to preventive maintenance of electrical systems and equipment used in industrial applications. The objective was to reduce the loss of life and property by correlating generally applicable procedures for preventative maintenance.

1973 — NFPA 70B-T, Tentative Recommended Practice for Electrical Equipment Maintenance, covered the benefits of an electrical preventive maintenance program, effective program development and planning.

1974 — The Tentative Recommended Practices document was revised to include fundamentals of electrical equipment maintenance, general maintenance requirements for various equipment types and a new appendix on instruction.

1975 — The tentative recommended practice was officially adopted as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance.

1977 — Chapters on electronic equipment, ground-fault protection, wiring devices and maintenance of electrical equipment subject to long intervals between shutdowns were added. New appendices covered NEMA plug and receptacle configurations and guidelines for long-term maintenance.

1983 — Chapters on cable tray systems, de-energizing and grounding equipment for maintenance personnel protection were added. An appendix on equipment storage and maintenance during construction was introduced.

1987 — This edition expanded to include distribution transformers and power transformers.

1990 — A new chapter on uninterruptible power supply was added.

1994 — New chapters covered power system studies, power quality, and vibration analysis related to rotating machinery.

1998 — This edition rewrote and expanded the power quality chapter, updated maintenance techniques for stationary batteries and infrared inspections, introduced special handling and disposal considerations, and focused on employee training for workplace safety.

2002 — The scope was revised to include preventive electronic and communication equipment maintenance. Chapters were added for grounding maintenance issues and gas-insulated substations. The power quality chapter included information on the latest technology in voltage fluctuation and a new annex suggested maintenance intervals for electrical equipment.

2006 — A new chapter was added emphasizing safety and commissioning the electrical system at a new facility. A chapter on reliability-centered maintenance was introduced, along with an extensive annex providing detailed reliability data on various types of electrical equipment.

2010 — Reorganization grouped similar topics, and chapters on testing and test methods for individual equipment types were added. A section on emergency preparedness and electrical system restoration, including outsourcing of equipment maintenance, was included. Personnel safety requirements were revised to reference NFPA 70E directly.

2013 — Four new chapters were added: electrical disaster recovery, photovoltaic systems, electrical vehicle charging systems, wind power electrical systems and associated equipment.

2016 — Torque recommendations were added to minimize electrical issues related to poor connections. Battery testing and maintenance recommendations were enhanced to provide greater detail on proper testing and safety considerations for those performing battery maintenance.

In tracing the chronology of NFPA 70B, we witness its continuous evolution, adapting to technological advancements and addressing diverse aspects of electrical equipment maintenance for enhanced safety and reliability.