In 1949, it was possible to determine oxygen by a particular reaction. The cross section of this reaction is 910 barns with thermal neutrons. The maximum energy of the tritons is 2.74 MeV. It is not very interesting to obtain tritons by this method because: 1) The nondestructive determination of oxygen in most materials is impossible for the thermal neutrons give too much radioactivity. 2) The triton beam presents a spectrum of energies. Oxygen determination in the bulk of the sample is then very difficult. 3) It is impossible to determine oxygen on perfectly clean surfaces since the surfaces are polluted during irradiation by contact with lithium or lithium salts. Therefore, the possibility of surface oxygen determination was studied by means of tritons accelerated in a Van de Graaff accelerator.