Sch 1C para 7
The error of indication for the volume metered after the durability test shall not exceed: — ± 6 % of the metered volume between Q 1 included and Q 2 excluded; — ± 2.5 % of the metered volume between Q 2 included and Q 4 included for water meters intended to meter water with a temperature between 0.1 °C and 30 °C,