Vacuum Decay Leak Test
The vacuum decay leak test is a non-destructive test method used to detect leaks in packaging to ensure container closure integrity (CCI).
The method can be used to identify gross defects and micron leaks in pharmaceutical, medical device and food packaging.
Vacuum decay leak testing is an approved ASTM F2338-09 standard test method and is a PDA recognized consensus standard for non-destructive detection of leaks in packages.
How does vacuum decay testing work?
To conduct a vacuum decay test, a container is placed in a tightly fitted chamber which is evacuated to a predetermined level of vacuum. After reaching the pre-set vacuum, a sensor measures the vacuum level over a predetermined time.
If the integrity of the container under test has been compromised (it has a leak), there will be a rise in pressure measured inside the chamber. This will result in a) a gross leak, if the vacuum doesn’t reach the pre-set vacuum level; b) a medium leak, if the vacuum level drops below a pre-set vacuum level during the test or c) a decay or micron leak, if the vacuum level exceeds the decay limit during the test time.
What type of containers can be tested using vacuum decay?
The vacuum decay test method can be used to test an array of non-porous flexible, rigid and semi-rigid packaging.
Non-lidded trays, and trays and cups sealed with non-porous lidding material can be tested if they can be masked or blocked during testing to create a completely sealed package. Only then can a change in pressure inside the chamber be measured, due to gas or vapor escaping from the masked or blocked tray or cup.
Packages that can be tested utilizing the vacuum decay test method include (but are not limited to):
- Rigid, non-porous containers including:
- Plastic screw capped bottles containing solids (tablets, capsules, powders) or liquids (with significant gas headspace volume)
- Glass or plastic vials containing liquids (with significant gas headspace volume) or solids (powders)
- Glass or plastic ampoules containing liquids
- Glass pre-filled syringes containing liquids or solids (lyophilized powders)
- Ophthalmic dropper tip bottles containing liquids
- Blow Fill Seal bottle or strip containing liquid
- Flexible, non-porous packages including bags and pouches containing solids (powders, medical devices)
- Sealed cups or trays containing solids (tablets, capsules, powder or devices)
- Non-lidded, empty cups or trays
Vacuum decay testing is also referenced in the revised USP 1207 guidance in which deterministic methods are preferred over probabilistic procedures such as the bubble test or blue bath method. The revised chapter will be applied to vials, ampoules, syringes, and bags.