http://yosemite.epa.gov/opa/admpress.nsf/0/D70B9C433C46FAA3852576A40058B1D4

The agency is proposing to set the “primary” standard, which protects
public health, at a level between 0.060 and 0.070 parts per million
(ppm) measured over eight hours. Children are at the greatest risk
from ozone, because their lungs are still developing, they are most
likely to be active outdoors, and they are more likely than adults to
have asthma. Adults with asthma or other lung diseases, and older
adults are also sensitive to ozone.

EPA is also proposing to set a separate “secondary” standard to
protect the environment, especially plants and trees. This seasonal
standard is designed to protect plants and trees from damage occurring
from repeated ozone exposure, which can reduce tree growth, damage
leaves, and increase susceptibility to disease.
-- 
John Gever
MedPage Today
tel. 1-304-243-0826
cell 1-304-780-9772
Skype 1-412-567-2949 (pre-arranged interviews only)
j.gever@medpagetoday.com or jgever@gmail.com
http://www.medpagetoday.com