1,215 ppm to PSU

1,215 ppm = 1.221 PSU

ppmPSU
1,200 ppm1.206
1,205 ppm1.211
1,210 ppm1.216
1,2151.221
1,220 ppm1.226
1,225 ppm1.231
1,230 ppm1.236

1215 ppm = 1.221 PSU

Formula

1 g/kg ≈ 1.0049 PSU · 1 mg/L ≈ 0.001 PSU · 1 ppm ≈ 0.001 PSU (dilute aqueous approximation)