399.5 mg/L = 399.5 ppm
| mg/L | ppm |
|---|---|
| 384.5 mg/L | 384.5 |
| 389.5 mg/L | 389.5 |
| 394.5 mg/L | 394.5 |
| 399.5 | 399.5 |
| 404.5 mg/L | 404.5 |
| 409.5 mg/L | 409.5 |
| 414.5 mg/L | 414.5 |
399.5 mg/L = 399.5 ppm
1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm