# ρ-Benzoquinone — US federal chemical regulatory reporting thresholds by program (CERCLA, EPCRA, CAA) For ρ-Benzoquinone, cas no. is 106-51-4; cercla rq (lbs) is 10; rcra waste number is U197; regulatory categories is 3,4, verified against its source on 2026-08-05. - **Substance:** ρ-Benzoquinone _(verified: appears in the quote below)_ - **CAS No.:** 106-51-4 _(verified: appears in the quote below)_ - **CERCLA RQ (lbs):** 10 _(verified: appears in the quote below)_ - **RCRA waste number:** U197 _(verified: appears in the quote below)_ - **Regulatory categories:** 3,4 _(verified: appears in the quote below)_ ## What the source says > ρ-Benzoquinone | 106-51-4 | 3,4 | U197 | 10 (4.54) ## Source - https://www.ecfr.gov/current/title-40/chapter-I/subchapter-J/part-302/section-302.4 Last verified: 2026-08-05. Review by: 2027-08-05. Part of [US federal chemical regulatory reporting thresholds by program (CERCLA, EPCRA, CAA)](https://referencesource.org/chemical-regulatory-reporting-thresholds/).