Four Highest Eight-Hour Ozone Concentrations in 2008

Use this form to retrieve the four highest eight-hour ozone concentration averages from data collected at DAQEM monitoring sites beginning December 14, 2005 through today. Although this is our most current data, it is not considered official until it has been certified by our technical staff. This information is updated hourly. All times shown are in Local Standard Time.

The table below lists the four highest daily maximum eight-hour ozone concentrations measured in 2008 in each community where the DAQEM measures ozone. Concentrations that are rated Moderate or higher are color-highlighted based on the EPA-defined Air Quality Index colors. (See Interpreting the AQI.) The fourth-highest average is in bold black (unless it is highlighted). All ozone measurements are in parts per billion. Times are shown in 24-hour format and correspond to the beginning of the eight hour average.

Use the selection boxes below to customize this report. You may select a different year or a different report format. If you want to cut and paste data from this web page into another application, such as a spreadsheet, select the comma-delimited format. Click on the Generate Report button once you have made your selections.

Year	Report Format

Highlight with AQI colors

Area	Monitoring Site	POC	Highest			Second Highest			Third Highest			Fourth Highest
Area	Monitoring Site	POC	Date	Time	Value	Date	Time	Value	Date	Time	Value	Date	Time	Value
Clark County
	E. Craig Road	1	08/27/2008	1100	80	08/14/2008	1100	77	08/16/2008	0900	74	05/31/2008	0900	71
	Apex	1	05/30/2008	1000	76	05/31/2008	0900	75	05/29/2008	1100	73	09/23/2008	1000	71
	Mesquite	1	05/11/2008	1200	71	04/30/2008	1300	71	05/31/2008	1100	70	06/03/2008	1300	69
	Paul Meyer	1	07/07/2008	1100	82	08/27/2008	1000	78	07/10/2008	1000	78	08/16/2008	0900	77
	Walter Johnson	1	07/07/2008	1100	83	07/10/2008	1000	78	08/27/2008	1000	76	08/16/2008	0900	76
	Lone Mountain	1	08/27/2008	1000	81	07/07/2008	1100	79	08/15/2008	1000	78	07/10/2008	0900	78
	Palo Verde	1	07/10/2008	0900	79	08/27/2008	1000	78	07/07/2008	1100	78	08/16/2008	1000	74
	Joe Neal	1	08/15/2008	1000	83	08/16/2008	0900	82	07/18/2008	1000	80	07/10/2008	0900	80
	Winterwood	1	08/14/2008	1100	75	08/27/2008	1000	73	08/16/2008	1100	72	07/18/2008	1000	71
	Boulder City	1	05/31/2008	0800	74	06/03/2008	1000	73	05/30/2008	1000	73	05/11/2008	1000	71
	Jean	1	05/11/2008	1100	78	08/15/2008	0900	75	05/30/2008	0900	74	05/03/2008	1100	74
	Orr	1	08/14/2008	1000	77	07/07/2008	1100	77	08/27/2008	1000	76	08/16/2008	0800	74
	JD Smith	1	08/27/2008	1000	69	08/14/2008	1100	69	05/30/2008	1000	69	05/31/2008	0900	68
POC (Parameter Occurrence Code): a code used to correctly separate data from multiple instruments at one site.

Interpreting the AQI

Air Quality Index

Each NAAQS pollutant has a separate AQI scale, with an AQI rating of 100 corresponding to the concentration of the Federal Standard for that pollutant. Additional information about the AQI and how it can be used is available from the EPA Exit

Place your mouse pointer over the scale displayed above to view information about the Air Quality Index, and each of the rating levels.

The actual index calculation is different for each parameter measured and is specified by the EPA. The following table shows the various breakpoints used in calculating the AQI.

AQI Breakpoint Definitions
AQI Range	1hr Ozone in ppm	8hr Ozone in ppm	8hr Carbon Monoxide in ppm	24hr Sulfur Dioxide in ppm	24hr PM-10 in ug/m3	24hr PM-2.5 in ug/m3
0 - 50	Not Defined	0 - 0.059	0 - 4.4	0 - 0.034	0 - 54	0 - 15.4
51 - 100	Not Defined	0.06 - 0.075	4.5 - 9.4	0.035 - 0.144	55 - 154	15.5 - 40.4
101 - 150	0.125 - 0.164	0.076 - 0.095	9.5 - 12.4	0.145 - 0.224	155 - 254	40.5 - 65.4
151 - 200	0.165 - 0.204	0.096 - 0.115	12.5 - 15.4	0.225 - 0.304	255 - 354	65.5 - 150.4
201 - 300	0.205 - 0.404	0.116 - 0.374	15.5 - 30.4	0.305 - 0.604	355 - 424	150.5 - 250.4
301 - 400	0.405 - 0.504	Not Defined	30.5 - 40.4	0.605 - 0.804	425 - 504	250.5 - 350.4
401 - 500	0.505 - 0.604	Not Defined	40.5 - 50.4	0.805 - 1.004	505 - 604	350.5 - 500.4
500	Not Defined	Not Defined	Not Defined	Not Defined	605 - 4999	500.5 - 999.9