Full explanation
Standard SGN for major Ukrainian fertilizers: prilled urea ≈ 160–180 (small granules from OSTCHEM tower prilling), granular urea ≈ 240–280 (more uniform, from Yara or Borealis), ammonium nitrate ≈ 250–300, NPK 16:16:16 ≈ 280–360, KCl ≈ 200–240. Agronomic impact: SGN <200 (prilled) = short granule flight in a spreader, max swath 18 m; SGN >280 = stable flight, 28–36 m. When buying a new pneumatic spreader (Amazone ZA-V, Kverneland Exacta) — the data table requires each fertilizer's SGN to adjust rates and vane angles. Second marker: UI (Uniformity Index) — UI 45+ = uniform, UI <40 = uneven fraction → switch to a simpler spreader or reduce working width. Source: fertilizer-kb.ts §calibration + ISO 5690.