If you work in cleanrooms long enough, you start to spot a pattern. Most conversations about viable air sampling focus on the “headline specifications” such as flow rate, portability, ease of use, maybe how a sampler fits into an isolator or a Grade A zone. All important, however when quality, validation, or an inspector gets involved, the conversation changes very quickly. It becomes less about what a supplier says their sampler does, and more about what they can prove, and how robust that proof is
That’s where validation at a government recognized laboratory really matters. The uncomfortable truth is that “validated” can mean a lot of things. In our industry, you’ll sometimes hear the word validated used loosely. Sometimes it means:
- We ran some tests in-house
- We tested it at a friendly lab
- We’ve got a summary slide somewhere
- It meets the standard because we’ve always sold it this way
None of that is necessarily dishonest, but it isn’t the same as independent validation carried out under controlled conditions by a lab with formal recognition and a reputation to protect. And when you’re using the data to support product release decisions, contamination investigations, or regulatory compliance, the difference is huge.
What does a Government Recognized Lab Actually Give You?
A government recognized lab brings three things that are hard to replicate elsewhere:
- Independence – They are not invested in your product looking good. Their job is to report what the performance truly is
- Scientific rigor – Test methods, controls, repeatability, documentation, all done properly, so the results stand up to scrutiny
- Credibility under pressure – When questions come, the validation doesn’t collapse into “trust us”. You have defensible data from an external authority
That’s not just a compliance tick-box. It’s operational confidence.
What “Good Validation” Looks Like in Practice
When we talk about validating an active air sampler properly, we mean examining the performance data to answer the questions that matter:
- Does it capture the particle sizes you care about? (Often discussed in terms of D50 and collection performance.)
- Does it preserve organism viability? It’s one thing to impact microbes onto agar; it’s another to do it in a way that doesn’t damage them so your results become artificially low.
- Is performance consistent over time and across conditions? Consistency is what makes a monitoring method usable and trustworthy.
- Is the evidence documented, transparent, and repeatable? A report you can put into a validation pack.
And importantly, can you explain it clearly to a quality team, a validation engineer, and (if needed) an inspector?
Why this Matters More Now Than it Did Five Years Ago
Aseptic manufacturing has become less forgiving. Annex 1 has pushed the whole industry toward tighter thinking around contamination control strategy, sampling rationale, and data integrity. That means the tolerance for anything but robust validation is shrinking. If you’re challenged on why you chose a method, or how you know it performs as claimed, you want answers that don’t rely on internal confidence or historical familiarity alone.
A Practical Question to Ask Any Supplier
Here’s a simple test that cuts through a lot of noise:
- “Can you share the full validation report and who carried it out ?”
- Not the brochure version. Not the one-slide summary. The real report
- If the response is vague, defensive, or “we don’t share that”, it’s worth pausing. Because if you can’t see the data, you can’t assess risk properly.
Where Slit-to-Agar Fits Into This
One reason U.K based Clean Air Monitoring Systems has stayed committed to slit-to-agar sampling technology is that it’s a method that can be validated and understood with clarity. It’s not a black box. You can test it. You can document it. You can explain it. And for cleanroom teams who need results that are not only accurate, but defensible, that matters.
Final thoughts
Validation is not a paperwork exercise. It’s what turns monitoring from “something we do” into “something we can rely on”. If you’re reviewing your viable monitoring setup, whether you’re in a new build, an isolator project, or simply trying to strengthen your contamination control strategy, it’s worth putting validation quality near the top of the list.
This article was originally published by Clean Air Monitoring Solutions (CAMS) based in the UK. It’s a good article and they make some very valid points. CAMS manufacture a range of specialized microbial air monitoring instruments which are based on slit to agar technology and are BEST in their class in the industry. These devices are highly sought after globally by leading pharmaceutical manufacturers and microbial air sampling professionals.
For more information on the CAMS range of air samplers, validation or anything in the above mentioned article, feel free to contact Alpha Scientific on 1300 025 780 Australia wide or email sales@alphascientific.com.au