What is the concentration range it can measure?

The method is designed for neat H₂O/D₂O mixtures across the full range from essentially pure H₂O (0 wt% D₂O) up to high-purity D₂O (>90 wt% D₂O). We specify performance over three ranges: 0–30 wt% D₂O, 30–90 wt% D₂O, and >90 wt% D₂O.