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AQS Change of Standard units

AQS Notes for August 8, 2012

Topics:

Change of standard units & Removal of ½ MDL substitution for PAHs and PM10 speciated metals

The standard units for Polycyclic Aromatic Hydrocarbons (PAHs) and PM10 speciated metals will change from microgram/meter3 to nanogram/meter3. Concurrently, ½ MDL substitution will also discontinue for these parameters. (Removal of ½ MDL substitution for certain parameters was proposed on June 23, 2011.) As part of this change, AQS will recompute the standard sample measurements and all the summaries (daily, quarterly, and annual) for these compounds.

For a parameter with ½ MDL substitution, the substitution occurs when AQS converts the reported sample measurement to the standard sample measurement. The reported sample measurement is always stored. However, if the reported value is below the method detection limit (MDL), then the standard sample measurement = ½ of the federal MDL.

See below for the parameter codes and descriptions of the pollutants involved.

The changes and the recalculations will occur August 11 - 12, 2012.

Please direct comments to AQSTeam@epa.gov.

AQS Parameter Code

Parameter Description

PAHs

17141

Naphthalene (TSP) STP

17147

Acenaphthene (TSP) STP

17148

Acenaphthylene (TSP) STP

17149

Fluorene (TSP) STP

17150

Phenanthrene (TSP) STP

17151

Anthracene (TSP) STP

17158

Retene (TSP) STP

17159

9-fluorenone (TSP) STP

17160

Cyclopenta[cd]pyrene (TSP) STP

17201

Fluoranthene (TSP) STP

17204

Pyrene (TSP) STP

17208

Chrysene (TSP) STP

17211

Coronene (TSP) STP

17212

Perylene (TSP) STP

17215

Benzo[a]anthracene (TSP) STP

17220

Benzo[b]fluoranthene (TSP) STP

17223

Benzo[k]fluoranthene (TSP) STP

17224

Benzo[e]pyrene (TSP) STP

17231

Dibenzo[a,h]anthracene (TSP) STP

17237

Benzo[g,h,i]perylene (TSP) STP

17242

Benzo[a]pyrene (TSP) STP

17243

Indeno[1,2,3-cd]pyrene (TSP) STP

PM10 speciated metals (at STP)

82101

Aluminum PM10 STP

82102

Antimony PM10 STP

82103

Arsenic PM10 STP

82105

Beryllium PM10 STP

82107

Barium PM10 STP

82110

Cadmium PM10 STP

82111

Calcium PM10 STP

82112

Chromium PM10 STP

82113

Cobalt PM10 STP

82114

Copper PM10 STP

82119

Chromium VI PM10 STP

82124

Gallium PM10 STP

82126

Iron PM10 STP

82127

Palladium PM10 STP

82131

Indium PM10 STP

82132

Manganese PM10 STP

82134

Molybdenum PM10 STP

82135

Molybdenum PM10 STP

82136

Nickel PM10 STP

82140

Magnesium PM10 STP

82142

Mercury PM10 STP

82146

Lanthanum PM10 STP

82154

Selenium PM10 STP

82160

Tin PM10 STP

82161

Titanium PM10 STP

82164

Vanadium PM10 STP

82166

Silver PM10 STP

82167

Zinc PM10 STP

82168

Strontium PM10 STP

82173

Thallium PM10 STP

82176

Rubidium PM10 STP

82179

Uranium PM10 STP

82180

Potassium PM10 STP

82183

Yttrium PM10 STP

82184

Sodium PM10 STP

82185

Zirconium PM10 STP

82190

Boron PM10 STP

PM10 speciated metals (at local conditions)

85102

Antimony PM10 LC

85103

Arsenic PM10 LC

85104

Aluminum PM10 LC

85105

Beryllium PM10 LC

85107

Barium PM10 LC

85110

Cadmium PM10 LC

85111

Calcium PM10 LC

85112

Chromium PM10 LC

85113

Cobalt PM10 LC

85114

Copper PM10 LC

85117

Cerium Pm10 Lc

85118

Cesium Pm10 Lc

85119

Chromium VI PM10 LC

85126

Iron PM10 LC

85131

Indium Pm10 Lc

85132

Manganese PM10 LC

85134

Molybdenum PM10 LC

85136

Nickel PM10 LC

85140

Magnesium PM10 LC

85142

Mercury PM10 LC

85154

Selenium PM10 LC

85160

Tin PM10 LC

85161

Titanium PM10 LC

85164

Vanadium PM10 LC

85166

Silver PM10 LC

85167

Zinc PM10 LC

85168

Strontium PM10 LC

85173

Thallium PM10 LC

85174

Thorium PM10 LC

85176

Rubidium PM10 LC

85179

Uranium PM10 LC

85180

Potassium PM10 LC

85183

Yttrium PM10 LC

85184

Sodium PM10 LC

85185

Zirconium PM10 LC

85302

Sodium Ion Pm10 Lc

85303

Potassium Ion Pm10 Lc