  Resistive Plate Chambers (RPCs) were used for the instrumentation of the iron
flux return of the BABAR detector as a muon system. Unfortunately the
efficiency of the original RPCs degraded rapidly with time. Limited Streamer
Tubes (LSTs) were chosen for an upgrade of the barrel portion of the detector.
  The phased installation started in summer 2004 with replacing two sextants of
the BABAR barrel muon system with LSTs. The modules for the remaining four
sextants are under long-term test at SLAC and ready for installation, expected
in 2006. The modules become inaccessible once installed in BABAR, so it is
critical to select only perfectly working tubes. To accomplish this a strong QC
system was established during the prototype phase, and fully implemented
throughout pre-production and construction. To spot any damage during
transport, the final modules are subjected to comprehensive tests at SLAC
immediately after arrival and kept under long-term test till installation into
BABAR. Details of these tests and results from long-term testing will be
discussed. Since spring 2005 the PEP-II accelerator is running and BABAR is
collecting data. First experience from data taking with the LSTs will be
presented and the performance of the detector discussed.
