# IEEE C57.12.52 — Which OSHA-recognized labs (NRTLs) can certify to a given test standard For IEEE C57.12.52, standard title is Sealed Dry-Type Power Transformers, 501 kVA and Larger, Three-Phase; status is listed as appropriate, recorded from its source on 2026-08-10. - **Test standard:** IEEE C57.12.52 _(verified: appears in the quote below)_ - **Standard title:** Sealed Dry-Type Power Transformers, 501 kVA and Larger, Three-Phase _(verified: appears in the quote below)_ - **Status:** listed as appropriate _(our reading, not quoted from the source)_ ## What the source says > IEEE C57.12.52 | Sealed Dry-Type Power Transformers, 501 kVA and Larger, Three-Phase | ## Source - https://www.osha.gov/nationally-recognized-testing-laboratory-program/list-standards Last verified: 2026-08-10. Review by: 2026-11-08. Part of [Which OSHA-recognized labs (NRTLs) can certify to a given test standard](https://referencesource.org/nrtl-recognized-test-standards/).