A collection tube can lose its vacuum if it stays on the shelf too long.

• A. True
• B. False
• C. Depends on the tube
• D. Not sure

Answer: (B)

The vacuum inside evacuated collection tubes is built to be stable while the tube remains unopened and intact. The negative pressure is sealed in during manufacturing, and proper storage (within the specified conditions and before the expiration date) keeps that vacuum from leaking on the shelf. Only if the tube is damaged—cracked, broken stopper, punctured, or otherwise compromised—or is past its expiration or stored improperly would the vacuum be affected. So, simply staying on the shelf does not cause the vacuum to be lost; hence the statement is false.