The Strange–Rahman–Smith equation is used in the cryoporometry method of measuring porosity. NMR cryoporometry is a recent technique for measuring total porosity and pore size distributions. NMRC is based on two equations : the Gibbs–Thomson equation, which maps the melting point depression to pore size, and the Strange–Rahman–Smith equation, which maps the melted signal amplitude at a particular temperature to pore volume.