We have two test facilities in production:

100000 - Use this for miscellaneous testing purposes. If your testing calls for PHI to be loaded to the database, have IT delete these records when you're done. 

100853 - This facility is used for demonstrations, at conferences or webinars, for example. Therefore, no PHI should be loaded to this facility. Keep in mind that even if you upload a file and delete it before it's added to the database, the log file with potential PHI is still visible.

Test data should not be loaded to any other facility in production. Such data would skew data shown on NRDR aggregate reports.