The U.S. Environmental Protection Agency (EPA) plans
to issue a final new health standard for sulfur dioxide (SO2). According
to the EPA, this one-hour health standard will protect millions of Americans
from short-term exposure to SO2, which is primarily emitted from
power plants and other industrial facilities. Exposure can aggravate asthma and
cause other respiratory difficulties; people with asthma, children, and the
elderly are especially vulnerable to the effects.
“We’re taking on an old problem in a new way, one designed to give all American
communities the clean air protections they deserve,” said EPA Administrator
Lisa P. Jackson. “Moving to a one-hour standard and monitoring in the areas
with the highest SO2 levels is the most efficient and effective way
to protect against sulfur dioxide pollution in the air we breathe. This is one
of many pollutants we’ve been able to significantly reduce through the Clean
Air Act, keeping people healthy, protecting our environment and growing our
economy. This new standard-the first in almost 40 years-will ensure continued
success in meeting these challenges.”
The EPA is setting the one-hour SO2
health standard at 75 parts per billion (ppb), a level designed to protect
against short-term exposures ranging from five minutes to 24 hours. The EPA is
revoking the current 24-hour and annual SO2 health standards because
the science indicates that short-term exposures are of greatest concern and the
existing standards would not provide additional health benefits.
Monitoring requirements for SO2 are also
being changed; the new requirements ensure that monitors will be placed where
SO2 emissions impact populated areas. Any new monitors required by
this rule must begin operating no later than January 1, 2013. The EPA is
expecting to use modeling as well as monitoring to determine compliance with
the new standard.
final rule also changes the Air Quality Index to reflect the revised SO2
standard. This change will improve states’ ability to alert the public when
short-term SO2 levels may affect their health.
For more information, visit www.epa.gov/air/sulfurdioxide