Can anyone offer information as to the 30-day expiration date rule applied to saline cubes? Does this only apply to routine patient testing? We use saline to make reagents and I need to determine how to out-date these reagents. For example - saline expires in 30 days but is used to make PBS (we give a 6-month out-date to refrigerated PBS); which in turn is used to make enzymes (another 6-month out-date). How can I document an expiration date 1 year longer than the raw materials used to make the reagents? Any help or clarity would be most appreciated!