40 CFR § 63.5728 - What standards must I meet for closed molding resin operations?

---
identifier: "/us/cfr/t40/s63.5728"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 63.5728 - What standards must I meet for closed molding resin operations?"
title_number: 40
title_name: "Protection of Environment"
section_number: "63.5728"
section_name: "What standards must I meet for closed molding resin operations?"
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"
---


# 63.5728 What standards must I meet for closed molding resin operations?

(a) If a resin application operation meets the definition of closed molding specified in § 63.5779, there is no requirement to reduce emissions from that operation.

(b) If the resin application operation does not meet the definition of closed molding, then you must comply with the limit for open molding resin operations specified in § 63.5698.

(c) Open molding resin operations that precede a closed molding operation must comply with the limit for open molding resin and gel coat operations specified in § 63.5698. Examples of these operations include gel coat or skin coat layers that are applied before lamination is performed by closed molding.