Arc Flash Mitigation in the Data Center

Overview

The article gives an overview of the OSHA and NFPA 70E arc flash requirements that apply to data centers. Published in the Uptime Institute Journal in 2015, it treats the subject from an operations point of view and explains how maintenance discipline in data centers helps compliance.

The hazard analysis section requires determining the arc flash boundary, the incident energy at working distance and the required personal protective equipment. Incident energy is measured in cal/cm2. A separate section covers the variables that affect incident energy, stressing that fatal burns can occur at more than 10 ft from an arc.

The energized work section explains that NFPA 70E and OSHA require proof that de-energized work would create a greater hazard before energized work is allowed. Data centers often face pressure to work live because of continuity expectations, and the article shows that this alone is not sufficient justification. It does not detail calculation methods such as IEEE 1584; related standards are mentioned only as references.

Key points

1. Arc flash hazard analysis must determine the arc flash boundary, incident energy at working distance and required PPE.
2. Incident energy is measured in cal/cm2.
3. Fatal burns can occur at distances greater than 10 ft from an arc.
4. NFPA 70E and OSHA require proof that de-energized work creates greater hazards before energized work is allowed.
5. Maintenance discipline in data centers helps with compliance.
6. The article covers hazard analysis, boundaries and the bar on energized work.
7. Related standards are NFPA 70E and IEEE 1584.

Using it in design

• Include an arc flash incident-energy study placeholder and a labelling output for each switchboard in the electrical module.
• Prefer topologies that allow de-energized maintenance (concurrently maintainable designs).
• Add to the design checklist that boards and isolation points are placed so maintenance can be done without needing a case for energized work.

Who should read it

Electrical designers, operations and maintenance teams, and health and safety officers.

Related standards

• NFPA 70E
• IEEE 1584

Publication details

Authors

E. Rafter

Publisher

Uptime Institute Journal (Uptime Institute)

Year

2015

Document language

English

Source type

Industry body

Access

Free to read

Licence

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

Citation