| County | Number of Days Exceeded |
|---|
Record Count: 18 |
| Box Elder | 5 |
|---|
| Cache | 1 |
|---|
| Davis | 8 |
|---|
| Salt Lake | 9 |
|---|
| San Juan | 1 |
|---|
| Tooele | 4 |
|---|
| Uintah | 0 |
|---|
| Utah | 6 |
|---|
| Washington | 3 |
|---|
| Weber | 8 |
|---|
Data Notes
These data include "exceptional events", such as high winds, fires, construction, fireworks, etc.Data Source
U.S. Environmental Protection Agency, Air Quality System (AQS)
Graph Views
- Number of days by county, Utah, 2021
- Number of Days by Year, Box Elder County, 2001-2021
- Number of Days by Year, Cache County, 2000-2021
- Number of Days by Year, Carbon County, 2011-2021
- Number of Days by Year, Davis County, 2000-2021
- Number of Days by Year, Duchesne County, 2011-2021
- Number of Days by Year, Garfield County, 2011-2021
- Number of Days by Year, Iron County, 2018-2021
- Number of Days by Year, Salt Lake County, 2000-2021
- Number of Days by Year, San Juan County, 2000-2021
- Number of Days by Year, Tooele County, 2005-2021
- Number of Days by Year, Uintah County, 2007-2021
- Number of Days by Year, Utah County, 2000-2021
- Number of Days by Year, Washington County, 2004-2021
- Number of Days by Year, Weber County, 2000-2021
- Number of Person-days by Year, Box Elder County, 2001-2021
- Number of Person-days by Year, Cache County, 2000-2021
- Number of Person-days by Year, Carbon County, 2011-2021
- Number of Person-days by Year, Davis County, 2000-2021
- Number of Person-days by Year, Duchesne County, 2011-2021
- Number of Person-days by Year, Garfield County, 2011-2021
- Number of Person-days by Year, Iron County, 2018-2021
- Number of Person-days by Year, Salt Lake County, 2000-2021
- Number of Person-days by Year, San Juan County, 2000-2021
- Number of Person-days by Year, Tooele County, 2005-2021
- Number of Person-days by Year, Uintah County, 2007-2021
- Number of Person-days by Year, Utah County, 2000-2021
- Number of Person-days by Year, Washington County, 2004-2021
- Number of Person-days by Year, Weber County, 2000-2021
Definition
The United States Environmental Protection Agency (EPA) ozone standard states that the 8-hour average ozone level should not exceed 0.070 ppm. These standard levels are often referred to as the National Ambient Air Quality Standards (NAAQS). This level is considered protective for most people and within the normal defensive capacities of the human respiratory system.^1-3^[[br]]
[[br]]
----
1. McDonnell, et al. (1997) Prediction of ozone-induced FEV1 changes: Effects of concentration, duration and ventilation. American Journal of Respiratory and Critical Care Medicine. Vol 156, 715-722.[[br]]
2. Mudway, et.al. (2001) Differences in basal airway antioxidant concentrations are not predictive of individual responsiveness to ozone: A comparison of healthy and mild asthmatic subjects. Free Radical Biology and Medicine, Vol 31, No. 8. 962-974.[[br]]
3. Mudway, I and Kelly, F. J. (2004) An investigation of inhaled ozone dose and the magnitude of airway inflammation in healthy adults. American Journal of Respiratory and Critical Care Medicine, Vol 169, 1089-1095.How We Calculated the Rates
| Numerator: | This Indicator Report contains the following variables:[[br]]
1. Number of days with maximum 8-hour average ozone concentrations above the National Ambient Air Quality Standards (NAAQS) by county[[br]]
2. Number of person-days with maximum 8-hour average ozone concentrations above the NAAQS by county |
| Denominator: | When applicable, the population was obtained from the IBIS query system for appropriate years by county. |
Date Indicator Content Last Updated: 10/28/2022
