40 CFR § 751.303 - Definitions.

---
identifier: "/us/cfr/t40/s751.303"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 751.303 - Definitions."
title_number: 40
title_name: "Protection of Environment"
section_number: "751.303"
section_name: "Definitions."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "R"
subchapter_name: "TOXIC SUBSTANCES CONTROL ACT"
part_number: "751"
part_name: "REGULATION OF CERTAIN CHEMICAL SUBSTANCES AND MIXTURES UNDER SECTION 6 OF THE TOXIC SUBSTANCES CONTROL ACT"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "15 U.S.C. 2605, 15 U.S.C. 2625(l)(4)."
regulatory_source: "84 FR 11435, Mar. 27, 2019, unless otherwise noted."
cfr_part: "751"
---


# 751.303 Definitions.

The definitions in subpart A of this part apply to this subpart unless otherwise specified in this section. In addition, the following definitions apply:

*Distribute in commerce* has the same meaning as in section 3 of the Act, except that the term does not include retailers for purposes of § 751.321 and § 751.323.

*Interim ECEL* means a concentration of airborne TCE of 0.2 parts per million (ppm) calculated as an eight (8)-hour time weighted average (TWA) that will be in place only for the timeframes indicated for specified conditions of use, after which prohibitions would take effect.

*Interim ECEL action level* means a concentration of airborne TCE of 0.1 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA).

*Site-limited* has the same meaning as in 40 CFR 711.3.