The possibility of the Ly{beta} fluorescence mechanism being operational in classical Be stars and thereby contributing to the strength of the OI 8446 {AA} line has been recognized for long. However this supposition needs to be quantified by comparing observed and predicted OI line ratios. In the present work, optical and near-infrared spectra of classical Be stars are presented. We analyse the observed strengths of the OI 7774, 8446, 11287 and 13165 {AA} lines which have been theoretically proposed as diagnostics for identifying the excitation mechanism. We have considered and examined the effects of Ly{beta} fluorescence, collisional excitation, recombination and continuum fluorescence on these OI line strengths. From our analysis it appears that the Ly{beta} fluorescence process is indeed operative in Be stars.
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