Helium Leak Detection

Test Principle

The detection principle relies on helium mass spectrometry. The sealed container is either filled with helium (introduced into the headspace before sealing) or externally flooded with helium under controlled conditions. A helium mass spectrometer leak detector measures any escaping helium that passes through leak pathways.

If the measured helium leak rate exceeds a pre-established threshold, the container closure system is deemed non-integral. Conversely, a helium leak rate below the threshold indicates integrity. 

Test Equipments in Our Lab

PTI 1915+, Zholion MC-H52

Regulatory Requirements

USP<1207>

USP <1207> explicitly lists tracer gas leak detection with helium as a deterministic leak test method.

USP <1207> states that deterministic leak test methods using laser-based gas headspace analysis and helium leakage are those with the highest sensitivities.

Helium leak detection is classified as a deterministic technique, which USP <1207> strongly recommends over traditional probabilistic methods (dye ingress, microbial challenge) due to higher sensitivity, objectivity, and reproducibility.

USP <1207> references ASTM F2391 as the recognised consensus standard for helium tracer gas leak testing for package systems.

Method validation is required to demonstrate reliable detection of leaks at the product-specific Maximum Allowable Leakage Limit (MALL). Helium leak detection's high sensitivity allows testing to the MALL of most products.

USP 382

USP <382> points directly to USP <1207> for container closure integrity testing methodologies.

System-level integrity assessment using deterministic CCIT methods — including helium leak detection, high-voltage leak detection, vacuum decay, and laser headspace analysis — is required by 1 December 2025.

Deterministic methods are strongly recommended over traditional probabilistic methods.

EU GMP Annex 1

EU GMP Annex 1 contains container closure integrity requirements that are met using deterministic methods, including helium leak detection.

Deterministic CCI methods — including vacuum decay, HVLD, and helium leak detection — deliver results aligned with USP <1207> and global standards for Annex 1 compliance.

Helium leak detection is frequently and successfully used to explore, develop, and validate assembly parameters, and studies can be developed to evaluate the impact of distribution and storage on integrity as well.

Helium leak testing allows for a quality-by-design approach to package integrity, thus reducing the tendency to "test in" quality downstream.

Container closure integrity validation is mandatory for all sterile products. Deterministic methods are recognised as compliant with Annex 1 integrity requirements.

Sterile Pharmaceutical Packaging System Integrity Guideline Principles (2024, China)

In June 2024, the Chinese Pharmacopoeia Commission released the "9628 Sterile Pharmaceutical Packaging System Integrity Guideline Principle" (second draft) and "9650 Sterile Pharmaceutical Packaging System Integrity Guideline Principle" (first draft). These guidelines include deterministic CCIT methods and refer to approaches consistent with USP <1207>.

The 9650 guideline defines deterministic leak test methods as those "based on a series of predictable physical phenomena to detect or measure leakage — based on easily controllable and monitorable physical/chemical techniques, providing objective, quantitative data".

The guidance states: "Sealing test methods can be divided into two categories: deterministic methods and probabilistic methods".

While the 9628/9650 guidelines explicitly list vacuum decay, high-voltage leak detection (HVLD), and laser headspace analysis, helium leak detection — as a tracer gas method — is recognised as an advanced deterministic CCIT method under the framework of high-sensitivity integrity testing.