40 CFR § 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants.
---
identifier: "/us/cfr/t40/s63.61"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 63.61 - Deletion of methyl ethyl ketone from the list of hazardous air pollutants."
title_number: 40
title_name: "Protection of Environment"
section_number: "63.61"
section_name: "Deletion of methyl ethyl ketone from the list of hazardous air pollutants."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "63"
part_name: "NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401"
regulatory_source: "57 FR 61992, Dec. 29, 1992, unless otherwise noted."
cfr_part: "63"
---
# 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants.
The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78-93-3) is deleted from the list of hazardous air pollutants established by 42 U.S.C. 7412(b)(1).
[70 FR 75059, Dec. 19, 2005]