- ANSI, American National Standards Institute
- ASHRAE Code, US Dept. of Energy Code Information
- DLF NE
- EPA Energy Star
- IP Protection Class Chart – Quick reference chart for IP Protection Classes.
- NEC – National Electric Code – News, summaries, code changes
- NEMA – National Electrical Manufacturers Association
- NEMA / IEC – A brief comparison of NEMA and IEC protection class codes (pdf).
- NFPA – National Fire Protection Association
- NYSERDA – NY State Energy Research & Development Authority