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Title 40

Displaying title 40, up to date as of 9/04/2026. Title 40 was last amended 9/04/2026.
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What This Subpart Covers

§ 63.2130 What is the purpose of this subpart?

This subpart establishes national emission limitations for hazardous air pollutants (HAP) emitted from manufacturers of nutritional yeast. This subpart also establishes requirements to demonstrate initial and continuous compliance with the emission limitations.

§ 63.2131 Am I subject to this subpart?

(a) You are subject to this subpart if you own or operate a nutritional yeast manufacturing facility that is, is located at, or is part of a major source of HAP emissions.

(1) A manufacturer of nutritional yeast is a facility that makes yeast for the purpose of becoming an ingredient in dough for bread or any other yeast-raised baked product, or for becoming a nutritional food additive intended for consumption by humans. A manufacturer of nutritional yeast does not include production of yeast intended for consumption by animals, such as an additive for livestock feed.

(2) A major source of HAP emissions is any stationary source or group of stationary sources located within a contiguous area and under common control that emits or has the potential to emit, considering controls, any single HAP at a rate of 9.07 megagrams (10 tons) or more per year or any combination of HAP at a rate of 22.68 megagrams (25 tons) or more per year.

(b) [Reserved]

§ 63.2132 What parts of my plant does this subpart cover?

(a) This subpart applies to each new, reconstructed, or existing “affected source” that produces Saccharomyces cerevisiae at a nutritional yeast manufacturing facility.

(b) The affected source is the collection of equipment used in the manufacture of the nutritional yeast species Saccharomyces cerevisiae. This collection of equipment includes fermentation vessels (fermenters), as described in paragraph (c) of this section. The collection of equipment used in the manufacture of the nutritional yeast species Candida utilis (torula yeast) is not part of the affected source.

(c) The emission limitations in this subpart apply to fermenters in the affected source that meet all of the criteria listed in paragraphs (c)(1) and (2) of this section.

(1) The fermenters are “fed-batch” as defined in § 63.2192.

(2) The fermenters are used to support one of the last three fermentation stages in a production run (i.e., third-to-last stage, second-to-last stage, and last stage), which may be referred to as “stock, first generation, and trade,” “seed, semi-seed, and commercial,” or “CB4, CB5, and CB6” stages.

(d) The emission limitations in this subpart do not apply to flask, pure-culture, yeasting-tank, or any other set-batch (as defined in § 63.2192) fermentation, and they do not apply to any operations after the last dewatering operation, such as filtration.

(e) The emission limitations in Table 1 to this subpart do not apply to fermenters during the production of specialty yeast (defined in § 63.2192).

(f) An affected source is a “new affected source” if you commenced construction of the affected source after October 19, 1998, and you met the applicability criteria in § 63.2131 at the time you commenced construction.

(g) An affected source is “reconstructed” if it meets the criteria for reconstruction as defined in § 63.2.

(h) An affected source is “existing” if it is not new or reconstructed.

§ 63.2133 When do I have to comply with this subpart?

(a) If you have a new or reconstructed affected source, then you must comply with paragraph (a)(1) or (2) of this section.

(1) If you start up your affected source before May 21, 2001, then you must comply with this subpart no later than May 21, 2001.

(2) If you start up your affected source on or after May 21, 2001, then you must comply with this subpart upon startup of your affected source.

(b) If you have an existing affected source, then you must comply with this subpart no later than May 21, 2004.

(c) If you have an area source that increases its emissions, or its potential to emit, so that it becomes a major source of HAP, then paragraphs (c)(1) and (2) of this section apply.

(1) Any portion of the existing facility that is a new affected source or a new reconstructed source must be in compliance with this subpart upon startup.

(2) All other parts of the affected source must be in compliance with this subpart by no later than 1 year after it becomes a major source.

(d) You must meet the notification requirements in § 63.2180 according to the schedule in § 63.2180 and in subpart A of this part.