On February 22, 2023, EPA published revisions to the national emission standard for hazardous air pollutants (NESHAP) for the Miscellaneous Coating Manufacturing (MCM), 40 CFR Part 63, Subpart HHHHH (“MCM NESHAP”) [88 Fed. Reg. 10842 (February 22, 2023)].

The new regulation will have almost an immediate effect, triggering new control technology and performance tests within the first twelve months. 

Scope of the Affected Source

Ethan WareEthan WareThe revised MCM NESHAP applies to all equipment used to manufacture coatings made with listed hazardous air pollutants (HAP) that are metals. The following equipment, at a minimum, are subject to the new regulation: (1) process vessels; (2) storage tanks for feedstocks and products; (3) components such as pumps, compressors, agitators, pressure relief devices, sampling connection systems, open-ended valves or lines, valves, connectors, and instrumentation systems; and (4) wastewater tanks and transfer racks. Cleaning operations are also part of an affected source if related to any of the covered equipment. 

The term “coatings” — as used in the new MCM NESHAP — is an important limiting factor of the new MCM NESHAP. As defined, the term applies to paint, ink, or adhesives made from resins, pigments, solvents, and/or other additives when the material is “produced by a manufacturing operation where materials are blended, mixed, diluted, or otherwise formulated.” See 40 CFR 63.8105 and 63.7985(b) (defining “Coating” as used in the MCM NESHAP). Absent these processes, the new MCM NESHAP does not apply.

The term does not include materials made in processes where a formulation component is “synthesized by chemical reaction or separation activity” and then transferred to another vessel where it is formulated to produce a material used as a coating if the synthesized or separated component is “not stored prior to formulation.” Id. Therefore, some coating manufacturing processes fall outside of the rulemaking. 

A good way to evaluate the applicability of any new NESHAP is to peruse the list of North American Industry Classification System (NAICS) codes subject to the rulemaking and listed in the preamble. In this case, the list of NAICS includes NAICS code 325510, Paint and Coating Manufacturing; NAICS code 325520, Adhesive and Sealant Manufacturing; and NAICS code 325910, Ink Manufacturing. Id. If your business involves formulating these products with an affected source, the new MCM NESHAP likely applies. 

The New Standards

Covered sources will not have much time to adjust to the new MCM NESHAP. New sources (those commencing construction after June 7, 2022) are subject to the MCM NESHAP immediately while existing sources (those constructed or reconstructed on or before June 7, 2022) must demonstrate compliance as early as February 22, 2024. Either way, the new guidelines require performance tests within the first year and new controls when coatings are being charged in process vessels. 

i. Performance Tests

Initial compliance tests are required for both new and existing sources under the MCM NESHAP. The required test methodology falls under EPA Method 5. The EPA Method can require the establishment of “operating ranges” for the control device, and those ranges may become enforceable emission limits. While an existing facility may rely on recent EPA Method 5 results, a repeat initial performance test conducted pursuant to EPA Method 5 must be made within the next five years (and every five years thereafter). A new source must demonstrate compliance within 180 days of a startup. 

The MCM NESHAP regulates the type of continuous monitoring allowed for covered emissions points, as well. An affected source may rely on a variety of systems to meet the requirement, including the use of an alarmed bag leak detection system, operation of an alarmed monitoring device (such as for pressure drop) against limits provided by the control device’s manufacturer, and operation of a continuous parameter monitoring system (CPMS). 

Facilities are required to continuously comply with the emission monitoring standards during all operations that emit metal HAP. These final amendments do not apply to pigments and other solids that are in paste, slurry, or liquid form. 

ii. Control Technology

The most expensive provision in the new requirements appears to be the upgrades plants will have to make for raw material application systems. New controls are required when process vessels are being charged with metal HAP-containing solids. For purposes of the new rule, a covered “process vessel” must have a capacity of 250 gallons or more, regardless of how much coatings are in-process at any one time. In addition, at new sources, both stationary and portable process vessels are subject to controls, while only stationary units are subject to the MCM NESHAP at existing sources. 

Existing sources (those constructed before June 7, 2022) may not exceed 0.014 grains per dry standard cubic foot (gr/dscf), while new sources are subject to emissions limits of 0.0079 gr/dscf. 

iii. Timing

It is important to note what the MCM NESHAP regulation does not do. Despite requests to the contrary, affected sources are not allowed more than one year to perform initial performance tests and comply with new controls. “[Covered sources] must conduct the initial or first periodic performance test before February 22, 2024, unless you are already required to complete a periodic performance test as a requirement of renewing your facility’s operating permit under 40 CFR part 70 or 71, and have conducted a performance test on or before February 22, 2024” 88 Fed. Reg. at 10849. Any existing MCM NESHAP source installing new controls will not likely meet this deadline, so immediate action may be necessary. A facility may request an additional two years to comply with the controls under 40 CFR § 63.6(i)(4)(ii) if the qualifying criteria are satisfied. 

Conclusion and Next Steps

Metal coating manufacturers do not have a lot of time to evaluate compliance with the new MCM NESHAP. The process can require new continuous monitoring technology, operational ranges, installation of particulate controls for certain process vessels, and performance of performance tests.

As a result, coating manufacturers covered by MCM NESHAP should take steps now to come into compliance with the new regulation: 

  • Step No. 1: Determine whether dry solid materials containing metal HAP are ever added to a covered process vessel. If not, advise operational personnel not to include dry solids without review and approval by environmental professionals. 
  • Step No. 2: In the event, the facility is covered because dry solids are added to the coating manufacturing process, the plant should (1) Confirm each covered process vessel has required control technology, which is operating while the metal HAP-containing dry solids are being added to the unit or submit a construction permit application to add the pollution control technology; .(2) Before February 22, 2024, perform an EPA approved performance tests on each affected control device (or provide results of a past qualifying test) and set operating parameters or otherwise meet the rule’s requirements for continuous demonstration of compliance; and (3) For any affected process vessel not currently controlled, the facility should install a PM control device or route emissions to an otherwise available PM control device.
  • Step No. 3: In the event, the plant confirms no dry solids are added to metal coating production, you should document the results of the technology review and be prepared to provide that information to the State or EPA when inspected.

88 Federal Register 10842 (February 22, 2023)


Ethan R. Ware is an attorney in Columbia, South Carolina. He manages the Environmental Law Practice Group of Williams Mullen with offices throughout Virginia and the Carolinas. He has a Bachelor of Science in Biology from Wofford College and a Juris Doctorate Law Degree from the University of South Carolina School of Law. He is ranked a Tier 1 attorney in Environmental Law with Chambers and has been included annually in Best Lawyers in America for more than 10 years. Ethan limits his practice to the representation of business and industry in Environmental and OSHA legal matters.