4 The record articles

Extension of a Wool Fiberglass Manufacturing Compliance Deadline

Posted: August 14th, 2017

Authors: All4 Staff 

The National Emissions Standards for Hazardous Air Pollutants (NESHAP) located at 40 CFR Part 63 Subpart NNN regulates hazardous air pollutants (HAPs) emitted from wool fiberglass manufacturing facilities.  The rule was first proposed in 1997 and finalized in its original form in 1999.  In 2011, amendments to Subpart NNN were proposed, and, after four years of public comment and hearings, the 2011 amendments were finalized in 2015.  The 2015 amendments included the following:

  • The establishment of emissions limits for chromium compounds.
  • The establishment of pollutant-specific emissions limits for certain HAPs (i.e., phenol and methanol) that were previously regulated under a surrogate emissions limit (i.e., formaldehyde) for flame attenuation (FA) lines.
  • The finalization of Generally Available Control Technologies (GACT) standards for gas-fired glass-melting furnaces
  • The removal of the startup, shutdown, and malfunction (SSM) provision.  (Editorial Note: This provision previously exempted emissions during SSM periods from the emissions limits of the rule.)
  • The addition of the requirement that the submittal of performance testing reports shall be made through the Electronic Reporting Tool (ERT).

The general takeaway is that the 2015 amendments increased the level of emissions control and environmental protection provided by Subpart NNN.

In July 2017, U.S. EPA took direct final action to amend a portion of Subpart NNN that affects flame attenuation (FA) lines at regulated facilities.  Under this action, sources subject to Subpart NNN are provided an additional year to comply with the emissions limits for FA lines. The Clean Air Act (CAA) stipulates that U.S. EPA can provide sources up to three additional years to comply with applicable emissions limits.  The July 2017 direct final rule extends the compliance date to the maximum of three years, as affected FA lines were initially provided only two years to comply with the emissions limits of Subpart NNN.  Unless U.S. EPA receives “significant adverse comment” by August 28, 2017, this amendment will become effective October 25, 2017.

Additionally, ALL4 has learned that Subpart NNN is currently being amended again to add methanol and phenol emission limits to the currently existing formaldehyde emission limits on Rotary Spin (RS) lines. This change is required under consent agreement, and is slated to be finalized by December 2017.

As with hundreds of other state and federal regulations, ALL4 will continue to track additional changes to Subpart NNN.  Please bookmark all4inc.com and subscribe to ALL4’s Air Quality Insider podcast for future updates.   If you have questions about this action or you’d like assistance complying with Subpart NNN, please reach out to ALL4 at 610-933-5246.


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