in the C# method that calls FbCommand, I added an optional parameter, IsolationLevel and set the default to IsolationLevel.Snapshot.  (  I think this provides the most optimistic environment and in the calling procedures where I need more isolation, I can always override it)

I start the transaction with this isolation level,

Then  I have a try/catch block where the FbCommand executes the procedure,   If an exception is thrown, it rolls the transaction back, otherwise it commits.

Also, both the FbTransaction and FbCommand are in C# using clause

Dixon