# FM 3990 — Which OSHA NRTL is recognized for which test standard: all 21 labs' scopes of recognition, cross-referenced For FM 3990, laboratory is FM Approvals; standard title is Less or nonflammable Liquid-Insulated Transformers, verified against its source on 2026-08-10. - **Laboratory:** FM Approvals _(verified: appears in the quote below)_ - **Standard number:** FM 3990 _(verified: appears in the quote below)_ - **Standard title:** Less or nonflammable Liquid-Insulated Transformers _(verified: appears in the quote below)_ ## What the source says > FM 3990 | Less or nonflammable Liquid-Insulated Transformers | ## Source - https://www.osha.gov/nationally-recognized-testing-laboratory-program/fm Last verified: 2026-08-10. Review by: 2026-12-08. Part of [Which OSHA NRTL is recognized for which test standard: all 21 labs' scopes of recognition, cross-referenced](https://referencesource.org/nrtl-recognition-scopes/).