277.5 g/kg = 278.86 PSU
| g/kg | PSU |
|---|---|
| 262.5 g/kg | 263.786 |
| 267.5 g/kg | 268.811 |
| 272.5 g/kg | 273.835 |
| 277.5 | 278.86 |
| 282.5 g/kg | 283.884 |
| 287.5 g/kg | 288.909 |
| 292.5 g/kg | 293.933 |
277.5 g/kg = 278.86 PSU
1 g/kg ≈ 1.0049 PSU · 1 mg/L ≈ 0.001 PSU · 1 ppm ≈ 0.001 PSU (dilute aqueous approximation)