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Risk and Technology Review of the National Emissions Standards for Hazardous Air Pollutants

The Clean Air Act requires EPA to regulate hazardous air pollutants, also known as air toxics, from categories of industrial facilities in two phases.

  • In the first  "technology-based" phase, EPA develops standards for controlling the emissions of air toxics from sources in an industry group. These Maximum Achievable Control Technology or MACT standards are based on emissions levels that are already being achieved by the best-controlled and lowest-emitting sources in an industry.
  • Within eight years of setting the MACT standards, the Clean Air Act directs EPA to assess the remaining health risks from each source category to determine whether the MACT standards protect public health with an ample margin of safety, and protect against adverse environmental effects. This second phase is a “risk-based” approach called residual risk. Here, the EPA must determine whether more health-protective standards are necessary.

Also, every eight years after setting the MACT standards, the Clean Air Act requires that EPA review and revise the standards, if necessary, to account for improvements in air pollution controls and/or prevention. 

RTR Status

Source Category
(Link to Regulatory and Supporting Information)
Proposed Rule Signed or Publication Date Final Rule Publication Date
Iron and Steel Foundries 10/16/2019  6/25/2020 (signed)
Miscellaneous Coating Manufacturing 9/4/2019  8/14/2020
Plywood and Composite Wood Products Manufacture 9/6/2019  8/13/2020
Misc. Organic NESHAP (MON) 12/17/2019  8/12/2020
Taconite Iron Ore Processing 9/25/2019   7/28/2020
Rubber Tire Manufacturing 10/30/2019 7/24/2020
Lime Manufacturing Plants 9/16/2019  7/24/2020
Integrated Iron and Steel Manufacturing 8/16/2019  7/13/2020
Site Remediation 9/3/2019 7/10/2020
Paper and Other Web Coating 9/19/2019  7/9/2020
Automobiles and Light-Duty Trucks, Miscellaneous Metal Parts, Plastic Parts Coatings 11/1/2019  7/8/2020
Organic Liquids Distribution 10/21/2019 

7/7/2020 

(Note: A correction notice was published on 7/10/2020)

Ethylene Production 10/9/2019  7/6/2020
Cellulose Products Manufacturing 9/9/2019  7/2/2020
Engine Test Cells/Stands 5/8/2019  6/3/2020
Hydrochloric Acid Production 2/4/2019  4/5/2020
Municipal Solid Waste Landfills 7/29/2019  3/26/2020
Boat Manufacturing and Reinforced Plastics Composites Production 5/17/2019 3/20/2020
Solvent Extraction for Vegetable Oil Production 6/27/2019 3/18/2020
Asphalt Processing and Asphalt Roofing Manufacturing 5/2/2019  3/12/2020
Stationary Combustion Turbines 4/12/2019  3/9/2020
Surface Coating of Metal Cans and Metal Coil 6/4/2019  2/25/2020
Surface Coating of Large Appliances, Surface Coating of Metal Furniture, and Printing, Coating, and Dyeing of Fabrics 9/12/2018 3/15/2019
Surface Coating of Wood Building Products 5/16/2018 3/4/2019
Surface Coating of Wood Building Products 5/16/2018 3/4/2019
Wet-Formed Fiberglass Mat Production 4/6/2018 2/28/2019
Leather Finishing 3/14/2018 2/12/2019
Friction Materials Manufacturing 5/3/2018 2/8/2019
Portland Cement Manufacturing 9/21/2017 7/25/2018
Nutritional Yeast Manufacturing 12/28/2016 10/16/2017
Publicly-Owned Treatment Works 12/27/2016 10/26/2017
Pulp and Paper Combustion Sources 12/30/2016 10/11/2017
Aerospace 2/17/2015 12/7/2015
Petroleum Refineries 6/30/2014 12/1/2015
Primary Aluminum 12/6/2011
Supplemental Proposal: 12/8/2014
10/15/2015
Secondary Aluminum 2/14/2012
Supplemental Proposal: 12/8/2014

9/18/2015

Phosphoric Acid Production 11/7/2014 8/19/2015
Phosphate Fertilizer Manufacturing 11/7/2014 8/19/2015
Wool Fiberglass 11/25/2011, 4/15/2013, and 11/13/2014 7/29/2015
Mineral Wool 11/25/2011, 4/15/2013, and 11/13/2014 7/29/2015
Ferroalloys Production 11/23/2011 and 10/6/2014 6/30/2015
Off-Site Waste Recovery Operations 5/30/2014 3/18/2015
Flexible Polyurethane Foam Production 11/4/2013 8/15/2014
Acrylic/ Modacrylic Fibers 1/9/2014 10/8/2014
Polycarbonates Production 1/9/2014 10/8/2014
Polymers and Resins III 1/9/2014 10/8/2014
Pesticide Active Ingredient Production 1/9/2012 3/27/2014
Polyether Polyols Production 1/9/2012 3/27/2014
Polymers and Resins IV (7 categories) 1/9/2012 3/27/2014
Steel Pickling 10/21/2010 and 2/8/2012 9/19/2012
Chromium Electroplating
-Hard Chromium Electroplating
-Decorative Chromium Electroplating
-Chromium Anodizing Tanks
10/21/2010 and 2/8/2012 9/19/2012
Pulp and Paper I and III 12/27/2011 9/11/2012
Oil and Natural Gas Production 8/23/2011 8/16/2012
Natural Gas Transmission and Storage 8/23/2011 8/16/2012
Secondary Lead Smelters 5/19/2011 1/5/2012
Shipbuilding and Ship Repair 12/21/2010 11/21/2011
Wood Furniture 12/21/2010 11/21/2011
Primary Lead Smelting 2/17/2011 11/15/2011
Marine Vessel Loading 10/21/2010 4/21/2011
Pharmaceuticals 10/21/2010 4/21/2011
Printing and Publishing 10/21/2010 4/21/2011
Polymers and Resins I
-Epichlorohydrin Elastomers
-Nitrile Butadiene Rubber
-Polybutadiene Rubber
-Styrene Butadiene Rubber and Latex
10/21/2010 4/21/2011
Polymers and Resins I
-Polysulfide Rubber
-Ethylene Propylene Rubber
-Butyl Rubber
-Neoprene
12/12/2007 12/16/2008
Polymers and Resins II
-Epoxy Resins
-Non-Nylon Polyamides
12/12/2007 12/16/2008
Generic MACT (GMACT) I
-Acetal Resins Production
-Hydrogen Fluoride Production
12/12/2007 12/16/2008
Halogenated Solvent Cleaning 12/14/2006 5/3/2007
Hazardous Organics NESHAP (HON) 6/14/2006 12/21/2006
Dry Cleaners
-Major Sources
-Area Sources
-Co-Residential
12/21/2005 7/27/2006
Industrial Process Cooling Towers 10/24/2005 4/7/2006
Ethylene Oxide Emission Standards for Sterilization Facilities 10/24/2005 4/7/2006
Magnetic Tape 10/24/2005 4/7/2006
Gasoline Distribution 8/10/2005 4/6/2006
Coke Ovens 8/9/2004 4/15/2005

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Future RTR Deadlines

Source Category
(Link to Technical Information)
Consent Decree or Court Ordered Date for Signature of Final Rule
Mercury Emissions from Mercury Cell Chlor-Alkali Plants 10/1/2021
Semiconductor Manufacturing 10/1/2021
Generic MACT II - Cyanide Chemicals Manufacturing 10/1/2021
Generic MACT II - Spandex Production 10/1/2021
Generic MACT II - Carbon Black Production 10/1/2021
Primary Copper Smelting 10/1/2021
Flexible Polyurethane Foam Fabrication Operations 10/1/2021
Refractory Products Manufacturing 10/1/2021
Primary Magnesium Refining 10/1/2021

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Technical and Supporting Information