40 CFR § 60.121a - Definitions.

---
identifier: "/us/cfr/t40/s60.121a"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 60.121a - Definitions."
title_number: 40
title_name: "Protection of Environment"
section_number: "60.121a"
section_name: "Definitions."
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"
---


# 60.121a Definitions.

As used in this subpart, all terms not defined herein shall have the meaning given them in the Act and in subpart A of this part.

*Blast furnace* means any furnace used to recover metal from slag.

*Lead* means elemental lead or alloys in which the predominant component is lead.

*Process fugitive emissions source* means a source of particulate matter (PM) emissions at a secondary lead smelter that is associated with lead smelting or refining including, but not limited to, smelting furnace charging points; smelting furnace lead and slag taps; pot and refining furnaces; and casting kettles.

*Reverberatory furnace* includes the following types of reverberatory furnaces: stationary, rotating, rocking, and tilting.

*Secondary lead smelter* means any facility producing lead from a lead-bearing scrap material by smelting to the metallic form.