Proficiency Testing Ranges

Listed below are the analytes contained within each sample for proficiency testing. The method detection limits to be used for determining the levels of these analytes should fall between the low and high limits listed below.

Complex Nutrients
PEI-028-2 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Kjeldahl nitrogen, total (TKN) 1, 2, 3, 4 1795	1.50	to	35.0	mg/L
Nitrogen, total 4 1866	1.50	to	35.0	mg/L
Phosphorus, total 1, 2, 3, 4 1910	0.500	to	10.0	mg/L

Demand
PEI-026 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Biochemical oxygen demand (BOD) 1, 3, 4 1530	15.0	to	250	mg/L
Carbonaceous BOD (CBOD) 1, 3, 4 1555	15.0	to	250	mg/L
Chemical oxygen demand (COD) 1, 3, 4 1565	30.0	to	250	mg/L
Total organic carbon (TOC) 1, 3, 4 2040	6.00	to	100	mg/L

Nitrite in Water
PEI-028-3 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Nitrite as N 1, 4 1840	0.400	to	4.00	mg/L

Oil and Grease
PEI-029 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Oil & Grease 1, 3, 4 1860	20.0	to	100	mg/L

pH
PEI-027-3 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
pH 1, 3, 4 1900	5.00	to	10.0	Units

Residue (Whole-Volume)
PEI-079 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Residue, total (TS) 1, 4 1950	140	to	675	mg/L
Residue-filterable (TDS) 1, 3, 4 1955	140	to	650	mg/L
Residue-nonfilterable (TSS) 1, 3, 4 1960	23.0	to	100	mg/L

Simple Nutrients
PEI-028-1 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Ammonia as N 1, 3, 4 1515	0.650	to	19.0	mg/L
Nitrate as N 1, 3, 4 1810	0.250	to	40.0	mg/L
Nitrate+nitrite as N 1, 4 1820	0.250	to	40.0	mg/L
Orthophosphate as P 1, 3, 4 1870	0.500	to	5.50	mg/L

Total Cyanide
PEI-031 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Cyanide-Screen () 1636	0.00	to	1.00	mg/L
Total cyanide 1, 3, 4 1645	0.100	to	1.00	mg/L

Total Phenolics
PEI-032 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Total phenolics 1, 3, 4 1905	0.0600	to	5.00	mg/L

Total Residual Chlorine
PEI-033 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Total residual chlorine 1, 3, 4 1940	0.500	to	3.00	mg/L

Trace Metals 1
PEI-034-1 WPCHEM
Study Type

Analyte	Low Limit		High Limit	Units
Aluminum, Al 1, 3, 4 1000	200	to	4000	µg/L
Arsenic, As 1, 3, 4 1010	70.0	to	900	µg/L
Beryllium, Be 1, 3, 4 1020	8.00	to	900	µg/L
Cadmium, Cd 1, 3, 4 1030	8.00	to	750	µg/L
Chromium, Cr (total) 1, 3, 4 1040	17.0	to	1000	µg/L
Cobalt, Co 1, 3, 4 1050	28.0	to	1000	µg/L
Copper, Cu 1, 3, 4 1055	40.0	to	900	µg/L
Iron, Fe 1, 3, 4 1070	200	to	4000	µg/L
Lead, Pb 1, 3, 4 1075	70.0	to	3000	µg/L
Lithium, Li 4 1080	0.00	to	1000	µg/L
Manganese, Mn 1, 3, 4 1090	70.0	to	4000	µg/L
Mercury, Hg 1, 3, 4 1095	2.00	to	30.0	µg/L
Nickel, Ni 1, 3, 4 1105	80.0	to	3000	µg/L
Selenium, Se 1, 3, 4 1140	90.0	to	2000	µg/L
Vanadium, V 1, 3, 4 1185	55.0	to	2000	µg/L
Zinc, Zn 1, 3, 4 1190	100	to	2000	µg/L

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Accreditied for study program by the following as indicated

1. NELAC
2. EPA
3. Other
4. A2LA