An invertible simple equation for computation of blood O2 dissociation relations

An equation that will represent blood O2 dissociation relations over the saturation range of 0-100% and be invertible is presented. The Hill equation is contained as a special case of this form. Determination of the four parameters of the equations by standard dissociation curves presented by Severinghaus gives an equation of improved accuracy when contrasted to previous treatments. A program for use of this equation with certain hand-held calculators is available.