| Standard reference sample most probable values for the Spring 2004 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-177 | |||||||||||
| Analyte = | Silver (Ag) | Aluminum (Al) | Arsenic (As) | Boron (B) | Barium (Ba) | ||||||
| MPV = | 0.100 | mg/L | 76.5 | mg/L | 3.30 | mg/L | 90.7 | mg/L | 40.8 | mg/L | |
| F-pseudosigma = | 0.016 | 5.26 | 0.264 | 4.22 | (4.54) | 1.26 | (2.04) | ||||
| n = | 13 | 41 | 39 | 35 | 50 | ||||||
| Analyte = | Beryllium (Be) | Calcium (Ca) | Cadmium (Cd) | Cobalt (Co) | Chromium (Cr) | ||||||
| MPV = | 1.00 | mg/L | 31.4 | mg/L | 2.50 | mg/L | 2.60 | mg/L | 8.50 | mg/L | |
| F-pseudosigma = | 0.074 | 1.26 | (1.57) | 0.126 | 0.141 | 0.493 | |||||
| n = | 34 | 58 | 49 | 34 | 47 | ||||||
| Analyte = | Copper (Cu) | Iron (Fe) | Potassium (K) | Lithium (Li) | Magnesium (Mg) | ||||||
| MPV = | 7.80 | mg/L | 12.3 | mg/L | 3.30 | mg/L | 15.8 | mg/L | 7.63 | mg/L | |
| F-pseudosigma = | 0.545 | 6.39 | 0.196 | 0.630 | (0.790) | 0.223 | (0.381) | ||||
| n = | 48 | 27 | 59 | 22 | 60 | ||||||
| Analyte = | Manganese (Mn) | Molybdenum (Mo) | Sodium (Na) | Nickel (Ni) | Lead (Pb) | ||||||
| MPV = | 346 | mg/L | 4.12 | mg/L | 37.2 | mg/L | 3.71 | mg/L | 4.24 | mg/L | |
| F-pseudosigma = | 13.6 | (17.3) | 0.282 | 1.42 | (1.86) | 0.445 | 0.348 | ||||
| n = | 53 | 33 | 58 | 38 | 47 | ||||||
| Analyte = | Antimony (Sb) | Selenium (Se) | Silica (SiO2) | Strontium (Sr) | Thallium (Tl) | ||||||
| MPV = | 1.80 | mg/L | 1.33 | mg/L | 10.6 | mg/L | 239 | mg/L | 1.57 | mg/L | |
| F-pseudosigma = | 0.182 | 0.304 | 0.420 | (0.530) | 7.71 | (12.0) | 0.089 | ||||
| n = | 24 | 28 | 36 | 41 | 27 | ||||||
| Analyte = | Uranium (U) | Vanadium (V) | Zinc (Zn) | ||||||||
| MPV = | 1.76 | mg/L | 1.18 | mg/L | 304 | mg/L | |||||
| F-pseudosigma = | 0.185 | 0.304 | 13.1 | (15.2) | |||||||
| n = | 21 | 24 | 56 | ||||||||
| M-170 | |||||||||||
| Analyte = | Alkalinity | Boron (B) | Calcium (Ca) | Chloride (Cl) | Fluoride (F) | ||||||
| MPV = | 29.5 | mg/L | 31.1 | mg/L | 5.74 | mg/L | 8.88 | mg/L | 0.254 | mg/L | |
| F-pseudosigma = | 1.63 | 2.74 | 0.252 | (0.287) | 0.586 | 0.0297 | |||||
| n = | 65 | 29 | 67 | 72 | 54 | ||||||
| Residue on | |||||||||||
| Analyte = | Potassium (K) | Magnesium (Mg) | Sodium (Na) | pH | Evaporation | ||||||
| MPV = | 2.09 | mg/L | 3.73 | mg/L | 9.45 | mg/L | 7.85 | 70.0 | mg/L | ||
| F-pseudosigma = | 0.104 | (0.105) | 0.145 | (0.187) | 0.341 | (0.473) | 0.341 | (0.392) | 6.67 | ||
| n = | 65 | 67 | 65 | 70 | 45 | ||||||
| Specific | Total Phosphorus | ||||||||||
| Analyte = | Silica (SiO2) | Sulfate (SO4) | Conductance | Strontium (Sr) | as P | ||||||
| MPV = | 11.5 | mg/L | 8.33 | mg/L | 113 | mS/cm | 42.6 | mg/L | 0.932 | mg/L | |
| F-pseudosigma = | 0.371 | (0.575) | 0.441 | 3.71 | (5.65) | 1.78 | (2.13) | 0.042 | (0.047) | ||
| n = | 45 | 64 | 65 | 37 | 51 | ||||||
| Analyte = | Vanadium (V) | ||||||||||
| MPV = | 2.91 | mg/L | |||||||||
| F-pseudosigma = | 0.326 | ||||||||||
| n = | 26 | ||||||||||
| N-81 | 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 = | 0.180 | mg/L | 0.200 | mg/L | 0.182 | mg/L | 0.184 | mg/L | 0.085 | mg/L | |
| F-pseudosigma = | 0.017 | 0.029 | 0.007 | (0.009) | 0.007 | (0.009) | 0.005 | ||||
| n = | 59 | 43 | 47 | 50 | 55 | ||||||
| Orthophosphate | |||||||||||
| Analyte = | as P (PO4-P) | ||||||||||
| MPV = | 0.074 | mg/L | |||||||||
| F-pseudosigma = | 0.004 | ||||||||||
| n = | 57 | ||||||||||
| N-82 | 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 = | 0.805 | mg/L | 0.835 | mg/L | 1.60 | mg/L | 1.67 | mg/L | 0.856 | mg/L | |
| F-pseudosigma = | 0.042 | 0.099 | 0.071 | (0.080) | 0.059 | (0.083) | 0.032 | (0.043) | |||
| n = | 58 | 45 | 51 | 56 | 58 | ||||||
| Orthophosphate | |||||||||||
| Analyte = | as P (PO4-P) | ||||||||||
| MPV = | 0.832 | mg/L | |||||||||
| F-pseudosigma = | 0.031 | (0.042) | |||||||||
| n = | 58 | ||||||||||
| P-42 | |||||||||||
| Analyte = | Calcium (Ca) | Chloride (Cl) | Fluoride (F) | Potassium (K) | Magnesium (Mg) | ||||||
| MPV = | 0.495 | mg/L | 6.12 | mg/L | 0.110 | mg/L | 0.325 | mg/L | 0.048 | mg/L | |
| F-pseudosigma = | 0.020 | (0.025) | 0.378 | 0.023 | 0.033 | 0.003 | |||||
| n = | 32 | 34 | 20 | 29 | 27 | ||||||
| Orthophosphate | Specific | ||||||||||
| Analyte = | Sodium (Na) | pH | as P (PO4-P) | Sulfate (SO4) | Conductance | ||||||
| MPV = | 0.304 | mg/L | 3.90 | 0.055 | mg/L | 0.344 | mg/L | 63.2 | mS/cm | ||
| F-pseudosigma = | 0.045 | 0.119 | (0.195) | 0.016 | 0.180 | 3.63 | |||||
| n = | 32 | 37 | 22 | 26 | 32 | ||||||
| Hg-38 | |||||||||||
| Analyte = | Mercury (Hg) | ||||||||||
| MPV = | 0.081 | mg/L | |||||||||
| F-pseudosigma = | 0.008 | ||||||||||
| n = | 14 | ||||||||||