On the unity of measurements https://likumi.lv/doc.php?id=42562
Cabinet Regulation No. 40 Regulations on the List of Measuring Instruments Subject to State Metrological Control ", with amendments http://likumi.lv/doc.php?id=151306
Cabinet Regulation No. 212 Metrological requirements for measuring instruments and the procedure for their metrological control https://likumi.lv/ta/id/281520-merisanas-lidzeklu-metrologiskas-prasibas-un-to-metrologiskas-kontroles-kartiba
Cabinet Regulation No. 624 Regulations on the Procedure for Metrological Control of Measuring Instruments and Marks for Initial Verification https://likumi.lv/ta/id/269947
Cabinet Regulation No. 664 Regulations on Metrological Requirements for Water Consumption Meters http://likumi.lv/doc.php?id=142369&from=off
Cabinet Regulation No. 667 Regulations on Metrological Requirements for Heat Meters http://likumi.lv/doc.php?mode=DOC&id=142371
Cabinet Regulation No. 981 Regulations on Re-Verification of Measuring Instruments, Verification Certificates and Verification Marks http://likumi.lv/doc.php?id=149301