  We report a reliable method to estimate the disorder broadening parameter
from the scaling of the gaps of the even and major odd denominator fractional
quantum Hall states of the second Landau level. We apply this technique to
several samples of vastly different densities and grown in different MBE
chambers. Excellent agreement is found between the estimated intrinsic and
numerically obtained energy gaps for the $\nu=5/2$ fractional quantum Hall
state. Futhermore, we quantify, for the first time, the dependence of the
intrinsic gap at $\nu=5/2$ on Landau level mixing.
