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		Ozone trends analyses of anthropogenically influenced monitoring sites in the United States and on worldwide background ozone monitoring sites				Read the introductory materials and begin the process of better understanding how the science is integrated with the standard-setting processes
		Grading the National Parks for ozone (smog) for 2015-2017				Learn about the effects of ozone on biological systems and how to characterize hourly averaged ozone concentrations in biologically meaningful terms
		Background ozone and its influence on the setting of the US EPA's ozone standards				Bridging the gap between ozone exposure and ozone dose: The importance of high hourly average concentrations and "effective" dose
		The use of different exposure metrics for human health and vegetation give different trend patterns when same hourly data are used				Learn about background ozone levels and why theoretical modeling estimates underestimate actual background concentrations
		Description of the W126 cumulative exposure index.				Co-occurrence patterns of ozone, sulfur dioxide, daily PM-2.5, and nitrogen dioxide
		Additional considerations involving the W126 exposure index for protecting vegetation.				A summary of concerns about the methodology utilized in the epidemiological studies for PM
		Dr. Lefohn's December 2, 2019 comments submitted to the Federal Docket on EPA's Integrated Science Assessment Ozone document.				Dr. Lefohn's December 16, 2019 comments submitted to the Federal Docket on EPA's Policy Assessment Ozone document.
		Dr. Lefohn's October 1, 2020 comments submitted to the Federal Docket on EPA's Proposed Primary and Secondary Ozone Standards.				Dr. Lefohn's December 14, 2021 comments submitted to the Federal Docket on EPA's Policy Assessment for the Reconsideration of the National Ambient Air Quality Standards for PM document
		Dr. Lefohn's May 30, 2022 comments submitted to the Federal Docket on EPA's Policy Assessment Ozone document on the Reconsideration of the Ozone Standards.				Dr. Lefohn's April 10, 2023 comments submitted to the Federal Docket on EPA's Second Draft Policy Assessment Ozone document on the Reconsideration of the Ozone Standards.

		It is not clear that reducing ozone-causing emissions will result in the attainment of the ozone standard as the level of the standard continues to be lowered				Review the latest sulfur dioxide, ozone, PM-10, PM-2.5, carbon monoxide, lead, and other maps
		Why a new human health standard may be needed to protect the public from ozone				Review the maps for all of the US EPA's criteria pollutant standards

	Spring in Montana	Grizzly Bear		Photographing the Performing Arts Worldwide Portfolio 1 - US Symphony Portfolio 2 - NZ Symphony Portfolio 3 - Ballet Portfolio 4 - Arts in Motion
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