  The LHC upgrade scheduled for 2018 is expected to significantly increase the
accelerator's luminosity, and as a result the radiation background rates in the
ATLAS Muon Spectrometer will increase too. Some of its components will have to
be replaced in order to cope with these high rates. Newly designed small-strip
Thin Gap chambers (sTGC) will replace them at the small wheel region. One of
the differences between the sTGC and the currently used TGC is the alignment of
the wires along the azimuthal direction. As a result, the outermost wires
approach the detector's edge with a small angle. Such a configuration may be a
cause for various problems. Two small dedicated chambers were built and tested
in order to study possible edge effects that may arise from the new
configuration. The sTGC appears to be stable and no spark have been observed,
yet some differences in the detector response near the edge is seen and further
studies should be carried out.
