40 CFR § 60.642 - Standards for sulfur dioxide.
---
identifier: "/us/cfr/t40/s60.642"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 60.642 - Standards for sulfur dioxide."
title_number: 40
title_name: "Protection of Environment"
section_number: "60.642"
section_name: "Standards for sulfur dioxide."
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"
---
# 60.642 Standards for sulfur dioxide.
(a) During the initial performance test required by § 60.8(b), each owner or operator shall achieve at a minimum, an SO<sub>2</sub> emission reduction efficiency (Z<sub>i</sub>) to be determined from table 1 based on the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility.
(b) After demonstrating compliance with the provisions of paragraph (a) of this section, the owner or operator shall achieve at a minimum, an SO<sub>2</sub> emission reduction efficiency (Z<sub>c</sub>) to be determined from table 2 based on the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility.