With the ozone season coming to an end, Houston recorded a record low 16 days that exceeded federal standards for ground level ozone. These gains may be short lived since the EPA is expected to implement tougher ozone standards adopted earlier this year. No one can say what may have contributed to the results, but the gains do come amid tougher regulations, cooler weather, higher use of fuel efficient cars and more use of existing mass transit systems in response to the high price of gasoline. The new standards will renew concerns over Houston air quality.

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