40 CFR 63.1653
§ 63.1653 Opacity standards.
United States · 40 CFR — Protection of Environment · Status: effective
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- Citation
- 40 CFR 63.1653, § 63.1653 Opacity standards, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/176114
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Full text
No owner or operator shall cause emissions exiting from a shop due solely to operations of any affected submerged arc furnace, to exceed 20 percent opacity for more than one 6-minute period during any performance test, with the following exceptions:
(a) Visible particulate emissions from a shop due solely to operation of a semi-closed submerged arc furnace, may exceed 20 percent opacity, measured as a 6-minute average, one time during any performance test, so long as the emissions never exceed 60 percent opacity, measured as a 6-minute average.
(b) Blowing taps, poling and oxygen lancing of the tap hole; burndowns associated with electrode measurements; and maintenance activities associated with submerged arc furnaces and casting operations are exempt from the opacity standards specified in this section.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.