# FM 3611 — Which OSHA NRTL is recognized for which test standard: all 21 labs' scopes of recognition, cross-referenced For FM 3611, laboratory is CSA Group Testing and Certification Inc; standard title is Electrical Equipment for Use in Class I, Division 2; Class II, Division 2; and Class III, Division 1 and 2 Hazardous Locations, verified against its source on 2026-08-10. - **Laboratory:** CSA Group Testing and Certification Inc. _(verified: appears in the quote below)_ - **Standard number:** FM 3611 _(verified: appears in the quote below)_ - **Standard title:** Electrical Equipment for Use in Class I, Division 2; Class II, Division 2; and Class III, Division 1 and 2 Hazardous Locations _(verified: appears in the quote below)_ ## What the source says > FM 3611 | Electrical Equipment for Use in Class I, Division 2; Class II, Division 2; and Class III, Division 1 and 2 Hazardous Locations | ## Source - https://www.osha.gov/nationally-recognized-testing-laboratory-program/csa 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/).