This part of CISPR 16 is designated a basic standard, which specifies the methods of measurement of disturbance phenomena in general in the frequency range 9 kHz to 18 GHz and especially of conducted disturbance phenomena in the frequency range 9 kHz to 30 MHz. CISPR 16-2 has been reorganised into 4 parts, to accommodate growth and easier maintenance. This first edition of CISPR 16-2-1, together with CISPR 16-2-2, CISPR 16-2-3 and CISPR 16-2-4, cancels and replaces the second edition of CISPR 16-2, published in 2003. It contains the relevant clauses of CISPR 16-2 without technical changes.