The prepared CALIBRATION solution is hermetically sealed in a bottle made of high-quality hard GLASS or polyethylene. Because the conductivity of a prepared calibration solution changes during long-term storage, it is important to check whether the conductivity of calibration solution stored for a long time is the same as that of newly prepared calibration solution before it is used. In addition, calibration solution must not be reused once it has been opened and LEFT exposed to the AIR.

The prepared calibration solution is hermetically sealed in a bottle made of high-quality hard glass or polyethylene. Because the conductivity of a prepared calibration solution changes during long-term storage, it is important to check whether the conductivity of calibration solution stored for a long time is the same as that of newly prepared calibration solution before it is used. In addition, calibration solution must not be reused once it has been opened and left exposed to the air.