Sentence examples for background levels of ozone from inspiring English sources
Some U.S. states are starting to be caught between rising background levels of ozone pollution and legal standards that continue to be ratcheted down.
In some U.S. cities especially those at higher elevations in the mountainous west naturally occurring background levels of ozone are starting to represent a significant fraction of the total.
We conducted analyses to examine the sensitivity of our results to a number of different assumptions about the form of the standard, background levels of ozone, methods for simulating attainment of the 8-hr ozone standard, and the choice of health effects and effect estimates from published epidemiologic studies.
In adjusting individual hourly ozone values to meet the target metric value, we assumed that there is no fixed background level of ozone for any particular hour and set the background to zero.
We did not see effect modification by region, even though the background levels of carbon monoxide, NO2, ozone, and particulate matter < 10 μm in aerodynamic diameter varied among the regions, with the San Bernardino area recording higher levels for most pollutants.
A continuous increase in the background level of tropospheric ozone (O3) has become a major challenge for present and future agricultural productivity at worldwide.
The high levels of ozone in this region may also be contributing to the background levels of airway disease (Harkema et al. 1993).
Background levels of genetic alterations.
The ionization air purifier initially increased the ozone concentration by 5 15 ppb from a background level of 5 ppb, while the ozone generator raised it by some 250 ppb, according to Nizkorodov.
Background: High ambient levels of ozone (O3) and fine particulate matter (PM2.5) are associated with cardiovascular morbidity and mortality, especially in people with preexisting cardiopulmonary diseases.
Additionally, because the U.S. EPA's current science assessment (U.S. EPA 2008c) identifies no threshold for the relationship between ozone exposure and premature mortality, our assessment underestimates the overall avoided premature mortality in regions where ozone concentrations fall below the assumed background level of 40 ppb.
