Our aluminium glazed porch door opens _outwards_ into the front garden,
and thinking ahead to local problems around here - we don't really want
to do open it fully that way unless the caller's business as been
identified.

The door has become a bit of a de-facto front door, but looking around
at door chains, guards and hotel latches - most of these suit doors that
open inwards.

For instance, simple though it looks, I don't think this will work.

Door Guard Chrome Plated
http://www.screwfix.com/prods/25152

Suggestions?

--
Adrian C