---
kind: "unit"
title: "40"
title_heading: "Protection of Environment"
key: "chI/subchC/part73"
level: "part"
label: "Part 73"
heading: "Sulfur Dioxide Allowance System"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/40/chI-subchC-part73"
sections_count: 41
---

# Part 73 — Sulfur Dioxide Allowance System

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-part73-subpartA.md)
- [Subpart B — Allowance Allocations](/cfr/40/chI-subchC-part73-subpartB.md)
- [Subpart C — Allowance Tracking System](/cfr/40/chI-subchC-part73-subpartC.md)
- [Subpart D — Allowance Transfers](/cfr/40/chI-subchC-part73-subpartD.md)
- [Subpart E — Auctions, Direct Sales, and Independent Power Producers Written Guarantee](/cfr/40/chI-subchC-part73-subpartE.md)
- [Subpart F — Energy Conservation and Renewable Energy Reserve](/cfr/40/chI-subchC-part73-subpartF.md)
- [Subpart G — Small Diesel Refineries](/cfr/40/chI-subchC-part73-subpartG.md)