Issue
There are two issues: proposed standard changes for ground-level ozone and for particulate
matter. The American Lung Association sued EPA to force a review of the standards.
EPA has completed a round of meetings and hearings to gather input and on November
27, 1996 issued the proposed standards. Hearings are now underway. EPA is scheduled
to announce a final decision on whether to change the standards in late June 1997.
NAAQ for Ozone
Ozone is a gas found throughout the atmosphere. Ozone pollution occurs when unnaturally
high concentrations of ozone accumulate near the ground which results from the reaction
of sunlight with a combination of ozone precursor chemicals, including Nox and VOCs.
Current:
.12 parts per million averaged over a one hour period with one exceedance allowed per yr.
Proposed Standard:
.08 parts per million measured over eight hours, possibly allowing more than one exceedance per yr.
EPA is also seeking comment on several other options, including ozone concentrations
of .09 parts per million measured over eight hours, as well as a range of ozone concentrations
from .07 to .12 parts per million measured over one hour, which is the current standard.
NAAQ for PM
Particulate matter is comprised of primary particles which include fugitive dust,
fuel combustion products, biogenic emissions and industrial process emissions and
the secondary particles which are transformed chemically in the atmosphere from gases
emitted by both stationary and mobile sources.
Current
The current standard is based on particulate matter whose diameter is 10 microns or smaller (PM-10) in concentrations of 50 micrograms per cubic meter annually and 150 micrograms per cubic meter daily.
Proposed Standard
2.5 microns or smaller (PM 2.5) in concentrations of 15 micrograms per cubic meter annually and 50 micrograms per cubic meter daily.
EPA also proposed as an option to tighten the current standards for PM-10 and
establishing a new standard for PM-2.5.
OVERVIEW
If either the ozone or the particulate matter standard is made more stringent, the
number of non-attainment areas nationwide would increase to possibly three or more
times the current number. A map of the potential for new areas in New York to record
violations and be designated non-attainment is attached along with a map of those
areas currently in non-attainment.
Strict new regulatory programs will be required in these non-attainment areas to
control Nox and VOCs (for ozone) and Nox, VOCs and SO2 (precursors that form particulate
matter 2.5 through chemical reactions in the atmosphere). Further changes may be
required in the composition of motor fuels, such as reduction of sulfur in gasoline
and diesel, as well as measures to reduce vehicle miles traveled.
Why the Debate Over the Changes Which Are Being Proposed
The EPA standards are in place to protect public health. The agency established a
Clean Air Scientific Advisory Committee (CASAC), a panel of independent scientists,
to assure that sound science was the basis for setting standards necessary to protect
public health. It is accurate, though a gross oversimplification, to summarize their
findings about the standards and the data to support changing the standards this
way:
Also refer to the white paper entitled Self-Regulation, Market Forces, Drive IAQ Industry.
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