Hanna Instruments pH 10.01 Calibration Solution 1 Liter HI7010/1LDetails HI7010 1L is a premium quality pH 10. 01 calibration buffer produced in accordance with ISO 3696 BS3978 standards using high purity salts, deionized water, certified weight checked balances, and Class A glassware in a temperature controlled environment monitored with certified thermometers. Reported values are accurate to + 0. 01 pH @ 25C and are traceable to NIST Standard Reference Materials (SRMs). Air tight bottle with tamper proof seal