- Take 10 empty tubes and screw the cap tightly
- Fill the tight tube with water
- Wipe the external surface of the tube thoroughly to make it dry
- Place the tube in an inverted position with filter paper fixed at the base of the cap
- Allow the tube to stand for 1 hour
- The filter paper shall not show any absorption of water at any time during the 1-hours test period
I am Maneesh Maurya a professional pharmaceutical blogger from India having rich experience in the pharmaceutical Quality control field.
