Clayton Animal Shelter, 77 Hunter Avenue, St. Louis
Site Operator: St. Louis County Department of Health, Air Pollution Monitoring Program
Updated: All data shown is historical this instrument was shut down in 2009.
National Ambient Air Quality Standard: (24-hour samples; one taken every third day) A three-year average of the 98th percentile 24-hour averages equal or greater than 35 ug/m3 (micrograms per cubic meter) and/or a three-year average of annual averages equal or greater than 15.0 ug/m3 (micrograms per cubic meter).
Exceedances allowed without a violation being recorded: Two percent of daily observations
Disclaimer: Yearly and quarterly data shown below has been subject to data review and validation procedures by the reporting agency. Monthly data and data shown graphically is raw, unreviewed and unvalidated data.
|Sampling ended July, Third Quarter 2009|
Updated: All data shown is historical this instrument was shut down in 2010.
Primary: 0.15 µg/m3
Secondary: Same as the primary standard
On Nov. 12, 2008, EPA substantially strengthened the National Ambient Air Quality Standards for lead (see 73 FR 66964). EPA lowered the level of the primary (health-based) standard from 1.5 micrograms per cubic meter (µg/m3) to 0.15 µg/m3, measured as total suspended particles. EPA also revised the secondary (welfare-based) standard to be identical to the primary standard.
The standard is based on the highest rolling three-month average over a period of three years and two months. The standard is met at a monitoring site when the three-month average is less than or equal to 0.15 μg/m3. For specific rules and technical information, consult 40 CFR Pt. 50, Appendix R.
Disclaimer: The following table is a summary of Lead data (through 2008) calculated using the previous Lead National Ambient Air Quality Standards regulations, which compares a quarterly average to1.5 μg/m3. Data was calculated using EPA standard conditions of ambient temperature and barometric pressure. Data in this table, from Jan. 1, 2009 to the present, is calculated at local conditions using daily average temperature and barometric pressure. All data in this table is historical and will not be updated.
|Instrument shut down 2010|