ISO 12917-2:2002 specifies a method for the calibration of horizontal cylindrical tanks having diameters greater than 2 m by means of internal measurements using an electro-optical distance-ranging instrument, and for the subsequent compilation of tank-capacity tables.

This method is known as the internal electro-optical distance-ranging (EODR) method.

ISO 12917-2:2002 is applicable to tanks inclined by up to 10 % from the horizontal, provided a correction is applied for the measured tilt.