| Parameter | Proficiency testing item C74A |
Uncertainty | Proficiency testing item C74B |
Uncertainty | Unit |
| 1,1-Dichloroethene | 0.406 | 0.022 | 2.92 | 0.15 | µg/L |
| Dichloromethane | 1.90 | 0.11 | 4.30 | 0.23 | µg/L |
| trans-1,2-Dichloroethene | 0.58 | 0.04 | 1.76 | 0.10 | µg/L |
| cis-1,2-Dichloroethene | <0.1 | - | 1.58 | 0.09 | µg/L |
| Trichloromethane | 0.74 | 0.04 | 2.82 | 0.15 | µg/L |
| 1,1,1-Trichloroethane | 0.54 | 0.03 | 1.55 | 0.08 | µg/L |
| Tetrachloromethane | <0.1 | - | 1.05 | 0.07 | µg/L |
| 1,2-Dichloroethane | 0.76 | 0.05 | 1.98 | 0.11 | µg/L |
| Trichloroethene | 1.51 | 0.08 | 3.01 | 0.16 | µg/L |
| Bromodichloromethane | 0.199 | 0.014 | 0.89 | 0.05 | µg/L |
| Tetrachloroethene | 0.92 | 0.05 | 2.43 | 0.13 | µg/L |
| Dibromochloromethane | 0.61 | 0.03 | 1.59 | 0.08 | µg/L |
| Tribromomethane | 0.416 | 0.023 | 1.30 | 0.07 | µg/L |