---
kind: "unit"
title: "40"
title_heading: "Protection of Environment"
key: "chI/subchC/part74"
level: "part"
label: "Part 74"
heading: "Sulfur Dioxide Opt-Ins"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/40/chI-subchC-part74"
sections_count: 31
---

# Part 74 — Sulfur Dioxide Opt-Ins

Title 40 C.F.R. — Protection of Environment › Chapter I — Environmental Protection Agency › Subchapter C — Air Programs

## Contents

- [Subpart A — Background and Summary](/cfr/40/chI-subchC-part74-subpartA.md)
- [Subpart B — Permitting Procedures](/cfr/40/chI-subchC-part74-subpartB.md)
- [Subpart C — Allowance Calculations for Combustion Sources](/cfr/40/chI-subchC-part74-subpartC.md)
- [Subpart D — Allowance Calculations for Process Sources [Reserved]](/cfr/40/chI-subchC-part74-subpartD.md)
- [Subpart E — Allowance Tracking and Transfer and End of Year Compliance](/cfr/40/chI-subchC-part74-subpartE.md)
- [Subpart F — Monitoring Emissions: Combustion Sources](/cfr/40/chI-subchC-part74-subpartF.md)
- [Subpart G — Monitoring Emissions: Process Sources [Reserved]](/cfr/40/chI-subchC-part74-subpartG.md)