NFPA 110, Standard for Emergency and Standby Power Systems

Overview

NFPA 110 is a performance standard for emergency and standby power systems that provide an alternate source when normal power fails. The systems it covers include power sources, transfer equipment, controls, supervisory equipment and accessory equipment. In data centres, particularly US projects, it is the usual reference for the performance, testing and maintenance of generator plant. This scope treats standby power as a system running from source to load rather than as a single machine.

The current edition is 2025; the next edition is expected in 2028 and is being prepared in the Annual 2027 revision cycle. According to NFPA's development page, the topics under revision include inspection, testing and maintenance. The record here rests only on NFPA's public standard development page. That inspection, testing and maintenance are among the topics shows that the operating process is a significant part of the standard. The revision calendar helps users plan edition changes in advance.

The full text was not read here, so details such as class, type and level definitions and test intervals must be taken from the original. The standard addresses the performance of the system as a whole, not individual generator products. On data centre projects, the document serves as a basis for accounting for operating and commissioning requirements at design stage.

Key points

1. Title: Standard for Emergency and Standby Power Systems.
2. The current edition is 2025; the next edition is 2028.
3. Covers performance requirements for systems that provide an alternate source when normal power fails.
4. Systems include power sources, transfer equipment, controls, supervisory and accessory equipment.
5. The next edition is in the Annual 2027 revision cycle; topics include inspection, testing and maintenance.
6. In data centres it is the reference for generator plant performance, testing and maintenance in US projects.

Using it in design

• In the generator module, capture the EPSS class (fuel run time), type (start time) and level on the generator object and size fuel storage to the class.
• Generate the acceptance and periodic test schedule (load bank, transfer tests) for commissioning.
• Cite it as the reference standard for generator performance and maintenance requirements on US projects.

Who should read it

Electrical engineers who design, commission and operate generator and standby power systems for data centres.

Related standards

• NFPA 111
• NFPA 70
• ISO 8528

Publication details

Authors

National Fire Protection Association

Publisher

NFPA

Year

2025

Document number

NFPA 110

Document language

English

Source type

Standard

Access

Citation only

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation