---
kind: "unit"
title: "40"
title_heading: "Protection of Environment"
key: "chI/subchN/part425"
level: "part"
label: "Part 425"
heading: "Leather Tanning and Finishing Point Source Category"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/40/chI-subchN-part425"
sections_count: 69
---

# Part 425 — Leather Tanning and Finishing Point Source Category

Title 40 C.F.R. — Protection of Environment › Chapter I — Environmental Protection Agency › Subchapter N — Effluent Guidelines and Standards

## Sections

- [§425.01. Applicability.](/cfr/40/425.01.md)
- [§425.02. General definitions.](/cfr/40/425.02.md)
- [§425.03. Sulfide analytical methods and applicability.](/cfr/40/425.03.md)
- [§425.04. Applicability of sulfide pretreatment standards.](/cfr/40/425.04.md)
- [§425.05. Compliance dates.](/cfr/40/425.05.md)
- [§425.06. Monitoring requirements.](/cfr/40/425.06.md)

## Contents

- [Subpart A — Hair Pulp, Chrome Tan, Retan-Wet Finish Subcategory](/cfr/40/chI-subchN-part425-subpartA.md)
- [Subpart B — Hair Save, Chrome Tan, Retan-Wet Finish Subcategory](/cfr/40/chI-subchN-part425-subpartB.md)
- [Subpart C — Hair Save or Pulp, Non-Chrome Tan, Retan-Wet Finish Subcategory](/cfr/40/chI-subchN-part425-subpartC.md)
- [Subpart D — Retan-Wet Finish-Sides Subcategory](/cfr/40/chI-subchN-part425-subpartD.md)
- [Subpart E — No Beamhouse Subcategory](/cfr/40/chI-subchN-part425-subpartE.md)
- [Subpart F — Through-the-Blue Subcategory](/cfr/40/chI-subchN-part425-subpartF.md)
- [Subpart G — Shearling Subcategory](/cfr/40/chI-subchN-part425-subpartG.md)
- [Subpart H — Pigskin Subcategory](/cfr/40/chI-subchN-part425-subpartH.md)
- [Subpart I — Retan-Wet Finish-Splits Subcategory](/cfr/40/chI-subchN-part425-subpartI.md)