In the initial phase of ITER operation, 4He plasmas could be used in order to avoid activating the machine. The main ICRH scenarios foreseen for ITER 4He plasmas are (3He) 4He and (H) 4He. ICRH experiments have been carried out on JET using 4He plasmas to validate these scenarios. At the same time, conditions for access to H-mode in plasmas of various isotope compositions from dominantly 4He to dominantly D have been studied. Experiments have also been carried out for the first time in 4He plasmas with the ICRF power added to 4He neutral beam injection at the third harmonic of 4He in order to produce a 4He tail for alpha particle studies.