This Gulf standard specifies a method of checking the calibration of moisture meters in service for measuring the moisture content of previously cleaned oilseeds, by checking several values or a range covering all the values for which the moisture meter is used. The checking of several values allows the verification that the moisture meter, at the values for which it is normally used, does not give an error, while the checking of a range covering all the values provides the information necessary for calibration of the moisture meter with a view to carrying out appropriate adjustments. Its application to colza (rape) seed, sunflower seed and soya beans has been verified.