Standard reference sample most probable values for the Fall 2003 inter-laboratory comparison
[MPV, most probable value; n, number of samples; mg/L, micrograms per liter; mg/L, milligrams per liter; mS/cm, microsiemens per centimeter at 25 degrees Celcius; ( ), rating criterion.]
T-175
Analyte = Silver (Ag) Aluminum (Al) Arsenic (As) Boron (B) Barium (Ba)
MPV = 1.85 mg/L 52.0 mg/L 7.38 mg/L 48.3 mg/L 18.0 mg/L
F-pseudosigma = 0.193 5.63 0.448 4.00 0.67 (0.90)
n = 33 46 43 37 49
Analyte = Beryllium (Be) Calcium (Ca) Cadmium (Cd) Cobalt (Co) Chromium (Cr)
MPV = 2.92 mg/L 8.76 mg/L 8.20 mg/L 7.44 mg/L 1.93 mg/L
F-pseudosigma = 0.148 0.241 (0.438) 0.334 (0.410) 0.326 (0.372) 0.133
n = 43 55 54 41 35
Analyte = Copper (Cu) Iron (Fe) Potassium (K) Lithium (Li) Magnesium (Mg)
MPV = 1.85 mg/L 39.0 mg/L 3.83 mg/L 3.20 mg/L 2.03 mg/L
F-pseudosigma = 0.189 4.89 0.133 (0.192) 0.214 0.089 (0.102)
n = 31 45 54 21 54
Analyte = Manganese (Mn) Molybdenum (Mo) Sodium (Na) Nickel (Ni) Lead (Pb)
MPV = 49.4 mg/L 1.79 mg/L 8.63 mg/L 3.18 mg/L 3.00 mg/L
F-pseudosigma = 2.08 (2.47) 0.104 0.385 (0.431) 0.193 0.219
n = 56 25 54 34 44
Analyte = Antimony (Sb) Selenium (Se) Silica (SiO2) Strontium (Sr) Thallium (Tl)
MPV = 1.90 mg/L 2.10 mg/L 5.60 mg/L 63.6 mg/L 1.97 mg/L
F-pseudosigma = 0.104 0.289 0.341 2.15 (3.18) 0.111
n = 26 28 37 42 31
Analyte = Uranium (U) Vanadium (V) Zinc (Zn)
MPV = 1.48 mg/L 2.94 mg/L 71.6 mg/L
F-pseudosigma = 0.117 0.234 2.97 (3.58)
n = 19 31 55
M-168
Analyte = Alkalinity Boron (B) Calcium (Ca) Chloride (Cl) Fluoride (F)
MPV = 28.2 mg/L 81.4 mg/L 11.1 mg/L 9.50 mg/L 0.840 mg/L
F-pseudosigma = 2.25 4.52 0.32 (0.56) 0.541 0.0485
n = 58 29 60 65 51
Residue on
Analyte = Potassium (K) Magnesium (Mg) Sodium (Na) pH Evaporation
MPV = 1.64 mg/L 7.70 mg/L 10.1 mg/L 9.30 108 mg/L
F-pseudosigma = 0.082 0.234 (0.385) 0.35 (0.51) 0.208 (0.465) 14.1
n = 56 59 57 57 40
Specific Total Phosphorus
Analyte = Silica (SiO2) Sulfate (SO4) Conductance Strontium (Sr) as P
MPV = 5.20 mg/L 25.0 mg/L 182 mS/cm 70.2 mg/L 0.132 mg/L
F-pseudosigma = 0.334 1.04 (1.25) 4.0 (9.1) 2.52 (3.51) 0.0133
n = 50 66 58 36 43
Analyte = Vanadium (V)
MPV = 7.80 mg/L
F-pseudosigma = 0.460
n = 25
N-79 Ammonia Ammonia + Nitrate Nitrite + Nitrate Total Phosphorus
Analyte = as N (NH3-N) Organic N as N as N (NO3-N) as N (NO2+NO3-N) as P
MPV = 0.100 mg/L 0.149 mg/L 0.130 mg/L 0.131 mg/L 0.149 mg/L
F-pseudosigma = 0.0096 0.0519 0.0100 0.0093 0.0096
n = 50 32 39 40 52
Orthophosphate
Analyte = as P (PO4-P)
MPV = 0.102 mg/L
F-pseudosigma = 0.0066
n = 51
N-80 Ammonia Ammonia + Nitrate Nitrite + Nitrate Total Phosphorus
Analyte = as N (NH3-N) Organic N as N as N (NO3-N) as N (NO2+NO3-N) as P
MPV = 0.620 mg/L 0.787 mg/L 0.893 mg/L 0.888 mg/L 1.00 mg/L
F-pseudosigma = 0.0578 0.0782 0.0363 (0.0447) 0.0352 (0.0444) 0.030 (0.050)
n = 49 36 42 39 48
Orthophosphate
Analyte = as P (PO4-P)
MPV = 0.788 mg/L
F-pseudosigma = 0.1312
n = 49
P-41
Analyte = Calcium (Ca) Chloride (Cl) Fluoride (F) Potassium (K) Magnesium (Mg)
MPV = 0.550 mg/L 5.88 mg/L 0.107 mg/L 0.072 mg/L 0.054 mg/L
F-pseudosigma = 0.0200 (0.0275) 0.296 0.0236 0.0141 0.0059
n = 27 29 18 16 22
Orthophosphate Specific
Analyte = Sodium (Na) pH as P (PO4-P) Sulfate (SO4) Conductance
MPV = 0.480 mg/L 3.94 0.046 mg/L 0.320 mg/L 58.7 mS/cm
F-pseudosigma = 0.0222 (0.0240) 0.082 (0.197) 0.0049 0.3551 2.30 (2.94)
n = 25 30 18 23 27
Hg-37
Analyte = Mercury (Hg)
MPV = 0.044 mg/L
F-pseudosigma = 0.0030
n = 14