DTS Package, global variable, test vs live?

Are global variable parameters in a DTS package specific to "only" that one package and do not effect other packages?

I need to add a variable to a test package but am worried that if I add this parameter it might affect the live production Table. There are two different servers on different sides of the firewall, there are two different databases and there are two tables but with different names, and there are DTS packages but they reference different tables in the query code.

So is it ok to add the global variable which would allow this DTS to delete recent records from the "test" version and it wont do anything to my live version?By the way I did check Microsoft's website for more details on DTS and variables. It looks as thought they're saying it is specific to only that dts, table and database. But it would be nice to confirm this with someone out there more experienced.

http://msdn2.microsoft.com/en-us/library/aa933470(SQL.80).aspxsqlsql