Universality of critical behavior in gases

$P\ensuremath{-}V\ensuremath{-}T$ data in the critical region of six fluids ($^{3}\mathrm{He}$, $^{4}\mathrm{He}$, Xe, ${\mathrm{O}}_{2}$, C${\mathrm{O}}_{2}$, and ${\mathrm{H}}_{2}$O) have been analyzed in terms of two scaled equations of state using the methods of statistical analysis. The results confirm the hypothesis of universality of critical behavior for these gases to within the current e…