This standard describes a technique for measuring the impairment of a TV picture due to random noise in a colour signal. It should be realized that other mechanisms can be present which introduce impairments that appear to be caused by random noise, but are not measured by this technique. Other techniques are necessary for measuring parameters such as moiré, time base error and cross-colour. The values which result from this measurement method make it possible to compare different video tape recorders, recording systems and video tapes for the random noise characteristics. This standard is intended for use with all IEC recognized video recording formats.