Typically control valve seat leakage is designated by the Fluid Controls Institute standard FCI 70-2 or IEC 534-4.  A cage style globe valve complies with Class II or perhaps class III.  Leakage Class II leaks like a sieve.  Classes IV, V and VI are regarded as tight shutoff, because they are tighter than class II and III.  Neither Class IV, V nor VI are bubble tight.  FCI 70-2 does not address fire safe issues.
I have an automated 16-inch butterfly valve out for inquiry.  I do not call this a shutdown valve but it is to shutoff cooling water.  I specified bubble-tight shuttof in the normal direction and Class VI in the reverse direction.  I also specified fire safe per API 607 as required for a butterfly valve per the line specification valves.
Generally, an emergency shutdown valve would be a separate item than the control valve.  It would also be operated by a different control system.  I prefer clear definitions of shutdown applications.  Typically we have equipment shutdowns, process shutdowns and perhaps a safety shutdown or an emergency shutdown.  My definition of an emergency shutdown is a fire on an offshore platform.  The control system would typically shut everything down, perhaps with exclusions of things like firewater pumps, emergency generators, etc.  A process shutdown may stop the inflow to a vessel with a high level or stop the pumps on a low level.

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