Technology
CCIT methods compared
Most leak test methods were developed for rigid containers such as vials and syringes. This page compares them, fairly and at method level, for flexible IV bags.
Why bags are different
A flexible container changes the question.
An IV bag moves, stretches and changes shape. It may be wet after autoclaving, sealed inside an over-wrap, divided into chambers or filled with several litres of solution.
A method that works well on a glass vial may lose sensitivity on a bag, need the bag to be dry or unwrapped, or destroy the unit it tests. USP <1207> asks manufacturers to choose a method that suits the product and its package.
At a glance
Method by method.
General characteristics as described in USP <1207> and common industry practice. Performance on a specific bag always depends on format, fill and condition.
| Method | Type | Non-destructive | Fit for flexible bags | Typical use |
|---|---|---|---|---|
| Probe Position Decay™ | Deterministic | Yes | Whole bag, wet or over-wrapped | Laboratory and 100% in-line |
| Vacuum decay | Deterministic | Yes | Limited by surface moisture and bag flexing | Mainly laboratory |
| Pressure decay | Deterministic | Yes | Better suited to rigid or empty containers | Laboratory and in-line |
| High-voltage leak detection (HVLD) | Deterministic | Yes | Needs a conductive liquid fill | Laboratory and in-line |
| Laser headspace analysis | Deterministic | Yes | Needs a gas headspace and a transparent wall | Laboratory and in-line |
| Helium mass spectrometry | Deterministic | Partly: tracer gas added | Very sensitive; mainly for development | Laboratory |
| Dye ingress | Probabilistic | No | Destroys the sample; operator reads the result | Laboratory |
| Bubble or water-bath test | Probabilistic | No | Operator-dependent; bag must be wetted | Laboratory |
This comparison is a general summary for review by ASTRACEC before publication. It names methods, not suppliers.
Choosing a method
Four questions to ask of any method.
Is it deterministic?
USP <1207> prefers methods that give a measured value against a limit, rather than a judgement by eye.
Does it keep the bag?
A non-destructive test can be applied to every bag and the good ones released.
Does it work as packed?
Wet surfaces, over-wraps and chambers should not need to be removed or prepared for the test.
Can it run at line speed?
EU GMP Annex 1 expects 100% integrity testing for containers closed by fusion, such as IV bags.
Send us your bags. We will show you the result.
A feasibility study on your own bag formats, with a written report your QA team can use.