FACT SHEET
Proposed Amendments to Air Toxics Standards for Wet-Formed Fiberglass Mat Production
ACTION
•	On March 19, 2018, the U.S. Environmental Protection Agency (EPA) signed proposed
amendments to the 2002 National Emission Standards for Hazardous Air Pollutants
(NESHAP) for Wet-Formed Fiberglass Mat Production.
•	EPA is proposing minor amendments to enhance the effectiveness of the rule by
improving compliance and implementation.
•	EPA issued the air toxics standards for Wet-Formed Fiberglass Mat Production on April
11, 2002. The rule applies to all drying and curing ovens at facilities that produce mat
made of glass fibers bonded with a formaldehyde-based resin. The finished mat product
is used for applications such as backing material for asphalt shingles and roll roofing.
•	Following a residual risk and technology review (RTR) conducted under the Clean Air Act
(CAA), with this action EPA is proposing to:
o Revise requirements for periods of startup, shutdown and malfunction (SSM) to
be consistent with recent court decisions;
o Require electronic reporting of performance test results;
o Reduce the frequency of compliance reports to a semiannual basis in all
instances; and
o Reduce parameter monitoring and recording requirements during periods when
the binder formulation being applied to glass fibers to form mat does not contain
any hazardous air pollutants (HAPs).
•	EPA will accept comment on the proposed amendments for 45 days after publication in
the Federal Register.
•	In accordance with the CAA, EPA is required to assess the risk remaining after the
promulgation of the final air toxics standards (2002). This is known as a residual risk
review. Based on the completed risk assessment, EPA has determined that risks from
the Wet-Formed Fiberglass Mat Production source category are acceptable and provide
an ample margin of safety to protect public health.
•	The CAA also requires EPA to assess, review and revise air toxics standards, as
necessary, taking into account developments in practices, processes and control
technologies. The technology review of the standards for Wet-Formed Fiberglass Mat
Production facilities did not identify any developments that would further reduce HAP
emissions beyond the original NESHAP.
1

-------
BACKGROUND
•	The CAA requires EPA to regulate toxic air pollutants, also known as air toxics, from
categories of industrial facilities in two phases.
•	The first phase is "technology-based," where EPA develops standards for controlling the
emissions of air toxics from sources in an industry group or "source category." These
maximum achievable control technology (MACT) standards are based on emissions
levels that are already being achieved by the best-controlled and lower-emitting sources
in an industry.
•	Within 8 years of setting the MACT standards, the CAA 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, EPA must determine whether more health-protective standards are
necessary.
•	Also, every 8 years after setting MACT standards, the CAA requires EPA to review and
revise the standards, if necessary, to account for improvements in air pollution controls
and/or prevention.
•	The Wet-Formed Fiberglass Mat Production NESHAP is one of 96 air toxic standards that
require 174 industry sectors to eliminate 1.7 million tons of 187 toxic air pollutants that
are listed by Congress in the CAA.
•	Currently, the EPA is subject to a court-order requiring that the final action on the Wet-
Formed Fiberglass Mat Production RTR be completed by December 31, 2018.
HOW TO COMMENT
•	The EPA will accept comment on the proposal for 45 days after publication in the
Federal Register. Comments, identified by Docket ID No. EPA-HQ-OAR-2004-0309, may
be submitted by one of the following methods:
o Go to www.regulations.gov and follow the online instructions for submitting
comments.
o Send comments by email to a-and-r-Docket@epa.gov, Attention Docket ID No.
EPA-HQ- OAR-2004-0309.
o Fax your comments to: (202) 566-9744, Attention Docket ID. No. EPA-HQ-OAR-
2004-0309.
o Mail your comments to: EPA Docket Center, Environmental Protection Agency,
Mail Code: 28221T, 1200 Pennsylvania Ave., NW, Washington, DC 20460,
Attention Docket ID. No. EPA-HQ-OAR-2004-0309.
o Deliver comments in person to: EPA Docket Center, 1301 Constitution Ave., NW,
Room 3334, Washington, DC. Note: In person deliveries (including courier
deliveries) are only accepted during the Docket's normal hours of operation.
Special arrangements should be made for deliveries of boxed information.
2

-------
FOR MORE INFORMATION
•	Interested parties can download a copy of the proposed rule notice from EPA's website
at the following address: https://www.epa.gov/stationary-sources-air-pollution/wet-
formed-fiberglass-mat-production-national-emission-standards.
•	Today's action and other background information are also available either electronically
at http://www.regulations.gov, EPA's electronic public docket and comment system, or
in hardcopy at the EPA Docket Center's Public Reading Room.
o The Public Reading Room is located at EPA Headquarters Library, room number
3334 in the EPA WJC West Building, 1301 Constitution Ave., NW, Washington,
DC. Hours of operation are 8:30 a.m. to 4:30 p.m. Eastern Standard Time,
Monday through Friday, excluding Federal holidays.
o Visitors are required to show photographic identification, pass through a metal
detector and sign the EPA visitor log. All visitor materials will be processed
through an X-ray machine as well. Visitors will be provided a badge that must be
visible at all times.
o Materials for this proposed action can be accessed using Docket ID No. EPA-HQ-
OAR-2004-0309.
•	For further technical information about the rule, contact Mary Johnson, EPA's Office of
Air Quality Planning and Standards, at (919) 541-5025 orjohnson.mary@epa.gov.
3

-------