40 CFR § 60.397 - Modifications.

---
identifier: "/us/cfr/t40/s60.397"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 60.397 - Modifications."
title_number: 40
title_name: "Protection of Environment"
section_number: "60.397"
section_name: "Modifications."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "60"
part_name: "STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401"
regulatory_source: "36 FR 24877, Dec. 23, 1971, unless otherwise noted."
cfr_part: "60"
---


# 60.397 Modifications.

The following physical or operational changes are not, by themselves, considered modifications of existing facilities:

(a) Changes as a result of model year changeovers or switches to larger cars.

(b) Changes in the application of the coatings to increase coating film thickness.