  We consider the space-time associated with the evaporation of a black hole by
quantum mechanical tunnelling events. It is shown that the surface through
which tunnelling occurs is distinct from the global event horizon, and that
this has consequences for the radiation reaching future null infinity. A
spherical collapse process is modelled, and the radiation expected to be
observed at future null infinity is calculated. It is shown that external
observers witness an evaporation process that begins as the tunnelling surface
is exposed, and ends as the collapsing object passes behind its event horizon.
The sensitivity of emitted radiation to the collapse process is illustrated.
