About Mission Critical Safety.
A practitioner's reference for electrical and occupational safety in data centers — built on US NFPA 70E, NFPA 70, NFPA 855 and OSHA, and written by the person who teaches this material about 25 times a year.
§ What this is
- A reference, not a summary. Every page is an interpretation of the standard applied to a specific room, task or phase in a data center.
- Answer-first. The answer sits in the first sixty words. The explanation follows.
- Cited. Every requirement carries its article or section number, so you can go and read it yourself.
- Data-center-specific. Every standards page carries a "what this means in a data center" block, because that is the part nobody else writes.
- Free. The tools have no login and no download.
§ Who writes it
Rick Hauf, CSP — Certified Safety Professional with more than 35 years in environmental health and safety, delivering NFPA 70E electrical safety training nationally. Roughly 25 classes a year. Training evaluations average 9.7 out of 10. Every technical page on this site is reviewed before it publishes. Full bio →
§ What it is not
This site is an interpretation of published consensus standards and federal regulations. It is not a substitute for them, and it is not an engineering study.
No incident energy value, boundary or PPE category shown here applies to your specific equipment. Those come from your own arc flash study, your employer's electrical safety program, and the published standard.
NFPA 70E® is a registered trademark of the National Fire Protection Association. This site is not affiliated with, endorsed by, or sponsored by NFPA or OSHA.
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