CFR > Title 40 > Chapter I > Subchapter N > Part 439 > General CFR > Title 40 > Chapter I > Subchapter N > Part 439 > General Current as of: 2024 | Check for updates | Other versions § 439.0 Applicability § 439.1 General definitions § 439.2 General monitoring requirements § 439.3 General pretreatment standards § 439.4 General limitation or standard for pH Ask a legal question, get an answer ASAP!Click here to chat with a lawyer about your rights.