---
kind: "unit"
title: "42"
title_heading: "The Public Health and Welfare"
key: "ch85/schI"
level: "subchapter"
label: "Subchapter I"
heading: "Programs and Activities"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/42/ch85-schI"
sections_count: 78
---

# Subchapter I — Programs and Activities

Title 42 — The Public Health and Welfare › Chapter 85 — Air Pollution Prevention and Control

## Contents

- [Part A — Air Quality and Emission Limitations](/usc/42/ch85-schI-ptA.md)
- [Part B — Ozone Protection](/usc/42/ch85-schI-ptB.md)
- [Part C — Prevention of Significant Deterioration of Air Quality](/usc/42/ch85-schI-ptC.md)
- [Part D — Plan Requirements for Nonattainment Areas](/usc/42/ch85-schI-ptD.md)