Modern pharma and MedTech production teams face a familiar tension: regulators expect robust, deterministic leak detection, yet excessive sensitivity can quietly erode yield, increase batch losses, and strain validation resources. Many manufacturers assume that higher sensitivity always equals higher quality. In reality, the best-performing lines balance regulatory needs with a sensitivity level appropriate for the product, risk class, and packaging format.
This article explains how over-testing occurs, why it harms operational and compliance performance, and how Nolek’s approach helps manufacturers align sensitivity with actual risk while keeping production stable and audit-ready.
Why Over-Testing Happens
Over-testing usually stems from well-intended attempts to protect patient safety. Teams want to guarantee sterility and integrity, particularly for parenterals and high-risk devices. However, not all products require sub-microlitre thresholds or the highest possible vacuum decay performance.
Common causes include:
- Misalignment between test specification and real-world failure modes
- Misinterpretation of USP <1207> expectations
- Applying one test limit across several packaging formats
- Pressure from internal QA teams to reduce defect risk without reviewing yield impact
When sensitivity is disproportionate to product risk, the test begins rejecting good parts. This increases false failures, slows release, and complicates investigations.
The Hidden Cost of Excessive Sensitivity
False rejects are not just an inconvenience. They create a measurable cost across production, validation, documentation, and compliance.
1. Yield loss and material waste
Each unnecessary reject means packaging, drug product, or sterilised device is discarded. In sterile product manufacturing, this cost escalates quickly.
2. Extended root-cause investigations
Every rejected batch or unit demands evidence, retesting, deviation reports, and QA sign-off. This reduces engineering and quality team capacity for improvement work.
3. Slower validation cycles
An overly tight limit means IQ/OQ/PQ work must prove repeatability at thresholds that are often unrealistic, increasing the number of runs required and extending qualification timelines.
Nolek’s systems are engineered specifically to support validation-heavy environments, helping to ease these pressures.
4. Line downtime and bottlenecks
False failures disrupt otherwise stable packaging or filling workflows. Even a small percentage of unnecessary rejects can stall high-throughput lines.
How to Set a Sensitivity Level Based on Real Risk
The goal is not to test less, but to test correctly. Manufacturers should link their sensitivity limits to:
- Product type (liquid vs solid, parenteral vs non-sterile)
- Packaging material (glass, polymer, BFS, foil-based)
- Intended shelf-life
- Known defect types (cracks, channel leaks, seal faults)
- Regulatory frameworks such as USP <1207> and Annex 1
Deterministic methods such as vacuum decay and pressure decay offer predictable performance without requiring helium or tracer gases. Nolek’s dry test methods and micro and sub-microlitre sensitivity provide the necessary resolution without adding contamination risk or unnecessary complexity .
Right-Sizing Sensitivity: A Practical Approach
A robust specification process follows four steps:
1. Map actual failure modes
Focus on defects that have historically resulted in sterility loss, particulates, or product compromise. Avoid designing limits around theoretical events that do not occur in production.
2. Attach sensitivity requirements to packaging geometry
Not all formats require the highest sensitivity. Polymer vials, multi-layer blisters, and syringes each behave differently during testing.
3. Validate limits that support repeatability
The chosen threshold must be reachable consistently during OQ and PQ. Nolek’s in-house instrument development ensures stable, repeatable performance during qualification.
4. Build in headroom for lifecycle drift
Even well-calibrated instruments will experience small shifts over time. Setting a limit too close to the physical noise floor guarantees future false rejects. Nolek’s stable pressure decay instruments help reduce drift risk and keep results consistent across long production cycles .
Why Nolek’s Approach Helps Prevent Over-Testing
Our Custom Engineered Solutions (CES) are designed for regulated, validation-driven environments where both sensitivity and stability matter.
Key advantages include:
- Tailored test methods matched to the actual product and risk profile
- High sensitivity without unnecessary complexity, such as helium handling
- Cleanroom-compatible, non-contaminating systems suitable for parenteral lines
- In-house developed pressure decay instruments that deliver stable, predictable thresholds over time
These elements ensure manufacturers meet regulatory expectations while protecting yield, uptime, and operational efficiency.
Wrapping Up
Higher sensitivity does not automatically mean better quality. The most advanced manufacturers now focus on right-sizing sensitivity, aligning testing limits with real-world risk and packaging behaviour. This improves yield, accelerates validation, and strengthens compliance performance.
By combining deterministic test methods, cleanroom-ready design, and validation-centred engineering, we can work with manufacturers to achieve the right balance between safety and efficiency.
