  A simple routine is proposed for monitoring the efficiency value of a low
pressure pentane filled multi-wire proportional chamber (MWPC) in long term
experiments. The proposed algorithm utilizes a two parameter approximation for
the background function. It is based on a linear approximation of the
background in the energy range of 4.8 to 10.0 MeV and an exponential
approximation of the neutron induced tail in the 1.5 to 4.2 MeV region. This
specific energy interval is used to measure the efficiency value. Prior to
discussing the algorithm, a description of the DGFRS-2 setup detection module
is provided. Additionally, an example of its application is presented for the
complete fusion of a heavy ion induced 232Th+48Ca = Ds complete fusion nuclear
reaction. Descriptions of two other two-parameter functional dependencies for
background approximations are also provided. A feature of this algorithm is
that there is no interruption of the main experiment for a calibration test
(reaction). An alternative scenario is considered in brief too. In consist of a
measurement of scattered target like ions in 30 to 45 MeV energy interval to
estimate an efficiency value.
