# UL 307A — Which OSHA NRTL is recognized for which test standard: all 21 labs' scopes of recognition, cross-referenced For UL 307A, laboratory is CSA Group Testing and Certification Inc; standard title is Liquid Fuel-Burning Heating Appliances for Manufactured Homes and Recreational Vehicles, verified against its source on 2026-08-10. - **Laboratory:** CSA Group Testing and Certification Inc. _(verified: appears in the quote below)_ - **Standard number:** UL 307A _(verified: appears in the quote below)_ - **Standard title:** Liquid Fuel-Burning Heating Appliances for Manufactured Homes and Recreational Vehicles _(verified: appears in the quote below)_ ## What the source says > UL 307A | Liquid Fuel-Burning Heating Appliances for Manufactured Homes and Recreational Vehicles | ## 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/).