  We present a new radio-selected sample of PNe from the CORNISH survey. This
is a radio continuum survey of the inner Galactic plane covering Galactic
longitude, $10^\circ <l< 65^\circ$ and latitude, $|b| < 1^\circ$ with a
resolution of 1.5$^{"}$ and sensitivity better than 0.4 mJy/beam. The radio
regime, being unbiased by dust extinction, allows for a more complete sample
selection, especially towards the Galactic mid-plane. Visual inspection of the
CORNISH data, in combination with data from multi-wavelength surveys of the
Galactic plane, allowed the CORNISH team to identify 169 candidate PNe. Here,
we explore the use of multi-wavelength diagnostic plots and analysis to verify
and classify the candidate PNe. We present the multi-wavelength properties of
this new PNe sample. We find 90 new PNe, of which 12 are newly discovered and
78 are newly classified as PN. A further 47 previously suspected PNe are
confirmed as such from the analysis presented here and 24 known PNe are
detected. Eight sources are classified as possible PNe or other source types.
Our sample includes a young sub-sample, with physical diameters < 0.12 pc,
brightness temperatures (> 1000 K) and located closer than 7 kpc. Within this
sample is a water-maser PN with a spectral index of $-0.55\pm 0.08$, which
indicates non-thermal radio emission. Such a radio-selected sample, unaffected
by extinction, will be particularly useful to compare with population synthesis
models and should contribute to the understanding of the formation and
evolution of PNe.
