Soil Proficiency Test Schedule
| 2024 SM Soil PT Study Schedule | ||
| Study Number | Study Opens | Study Closes |
| SM-140 | Feb. 6, 2024 | March 21, 2024 |
| SM-141 | March 26, 2024 | May 9, 2024 |
| SM-142 | Aug. 20, 2024 | Oct. 3, 2024 |
| SM-143 | Oct. 21, 2024 | Dec. 4, 2024 |
Analyte
| Bromide | 10.0-100 mg/kg |
| Chloride | 200-1000 mg/kg |
| Fluoride | 25.0-500 mg/kg |
| Nitrate as N | 25.0-500 mg/kg |
| Nitrite as N | 25.0-500 mg/kg |
| Sulfate | 25.0-2000 mg/kg |
| Orthophosphate as P | 25.0-500 mg/kg |
| Nitrate+Nitrite as N | 50.0-1000 mg/kg |
