The HL-LHC phase will be a challenge for the existing CMS RPC system, as the expected
operating conditions are much higher with respect to those for which the detectors have been
designed. In addition, this could introduce non-recoverable aging effects, which can alter the
detector properties. A longevity test is therefore needed to estimate the impact of HL-LHC
conditions on the RPC detector performance. This will allow the validation of the RPC system for
the expected harsher background conditions. A dedicated long-term irradiation program, designed
to emulate the HL-LHC operational conditions, started in 2016 at the CERN Gamma Irradiation
Facility (GIF++). A few RPC detectors are exposed to intense gamma radiation and their main
detector parameters (currents, rate, resistivity) are continuously monitored as a function of the
collected integrated charge. The detector performance has also been studied with muon beams.
The latest results of the irradiation tests are presented

