  This paper reports on the performance of Resistive Plate Chambers (RPCs) as
function of the gas flow rate through the chambers and of environmental
conditions, such as atmospheric pressure, ambient temperature and air humidity.
The chambers are read out by pads with an area of 1 x 1 cm2 and a 1-bit
resolution per pad. The performance measures include the noise rate as well as
the detection efficiency and pad multiplicity for cosmic rays. The measurements
extended over a period of almost one year and are sensitive to possible
long-term aging effects.
