Well, yes. It depends on what you want to do then. If this testing really requires to promote the standby then you will need to take a new fresh base backup knowing that you are using 9.2.
if the standby is running on a file system with snapshotting (like zfs), and the master is doing WAL archiving, you could, in theory, pause the replication and snapshot the slave, do read/write tests on the slave, then restore that snapshot and resume replication, pulling from the WAL archive til it catches up.