This Recommendation belongs to a set of Recommendations describing the test methods to determine technical parameters of radio monitoring receivers that are important for the users of these receivers. When the described methods are followed by manufacturers, comparing different receivers is made easier. This Recommendation specifies the test procedure for the determination of the IP3 of a monitoring receiver. This test procedure definition is recommended to all the manufacturers, with the advantage for the users of such receivers, that an easier and more objective assessment of product quality is possible.