The plans of applications of the second Polish nuclear research reactor MARIA were developed in 1964 in the Institute for Nuclear Research. It was assumed that the reactor should provide means for following activities:
   neutron and condensed matter research with the neutron beams;
   radiation chemistry research;
   nuclear materials research;
   radioisotopes production;
   application of the radiation emitted by spent fuel assemblies;
   production and application of short-life radioisotopes;
   studies in nuclear reactor engineering and technology.
  The first design of the second Polish nuclear research reactor was completed on November 20, 1965 in the Office of Nuclear Technology Studies and Design PROATOM.
  The construction of the reactor started on June 16, 1970. The first critical state of the reactor core was reached on December, 1974. The reactor was named MARIA in memory of Maria Curie-Skłodowska.
  Reactor MARIA was operated from 1975 to 1985. In the middle of 1985 the work started to refurbished the reactor with:
   new block control system SAKOR-B,
   survey and tests of graphite blocks of neutron reflector,
   additional beryllium blocks,
   shielding of the pressure stabilizer,
   refurbishment of the cooling system,
   refurbishment of air conditioning system,
   system of temperature and hydraulics monitoring in fuel channels.
  After Chernobyl new principles have been applied in the analyses of nuclear safety. On the basis of these the passive safety system of flooding the fuel channels with pool water in emergency has been introduced in the reactor MARIA. The new design of the neutron beam tubes has been introduced.
  The reactor has been restarted after refurbishment in December 1992 and is operated on regular basis since then. The reactor can be in service at least to 2020 when the next refurbishment will be considered to prolong its operation to 2060.
  Working time of the reactor MARIA.