X. Workshop on Resistive Plate Chambers and Related Detectors

The trigger for the ALICE muon spectrometer will be issued by 72 single-gap, low resistivity bakelite RPCs, arranged in two stations of two planes each. The area covered by one plane is 5.5x6.5 m2. In order to operate RPCs both in streamer and avalanche mode, two dierent gas mixtures have been developed. After installation in the ALICE experimental hall, the detectors have undergone a two year commissioning phase, both with cosmic rays and during early LHC operation, and they are now ready for physics data taking. The results of the commissioning both in streamer and avalanche mode will be presented, with particular regard to the RPC performance in terms of eficiency, current and counting rate. The detector behaviour during the first physics run, expected by end 2009, will also be highlighted.