Views: 100 Author: Site Editor Publish Time: 2026-09-29 Origin: Site
A practical guide for workplace designers, facility managers, and procurement teams.
You've seen the spec sheets. "30dB sound reduction." "Class A acoustic performance." "Soundproof pod."
But what do these numbers actually mean？ And more importantly — how do you verify them before you specify a product for your workplace？
This guide breaks down the science, the standards, and the questions you should be asking every supplier.
This is the most common misunderstanding in workplace acoustics.
No pod is completely silent inside. And no pod creates absolute silence outside. What acoustic pods actually deliver is speech privacy — the ability to hold a conversation without being overheard, and to work without being distracted by nearby speech.
The goal is not zero sound. The goal is unintelligible speech outside the pod, and comfortable focus inside it.
When a supplier claims "100% soundproof," that's a red flag. Physics doesn't work that way.
ISO 23351-1 is the international standard specifically developed for acoustic privacy in open office pods and furniture.
It measures something called SPLR — Speech Level Reduction.
In simple terms： SPLR tells you how much a pod reduces the level of speech passing through it. A higher SPLR means better speech privacy.
The classification system works roughly like this：
When you see "30.1 dB, ISO 23351-1", it means the pod has been tested to the highest classification under this standard.
Important： ISO 23351-1 is not the same as ISO 3382-2. The latter measures reverberation time in open-plan offices — a different acoustic property entirely. Don't let suppliers mix them up.
We've all seen it： someone stands outside a pod with a phone app, claps their hands, and declares the pod "not soundproof."
This is not a valid test.
Why？
Phone decibel apps are not calibrated instruments.
They measure total sound pressure level, not speech intelligibility.
They don't account for frequency-specific attenuation.
Background noise in the test environment is uncontrolled.
Laboratory testing under ISO 23351-1 uses：
Calibrated microphones and speakers
Controlled background noise levels
Standardised speech signals
Frequency-band analysis
Third-party verification
If a supplier can't provide a test report from an accredited lab, their acoustic claims are marketing — not engineering.
Speech privacy is not about blocking all sound. It's about making sure that：
People inside the pod can speak freely without being overheard.
People outside the pod are not distracted by muffled speech.
This is why SPLR is measured specifically for speech frequencies — not just overall noise reduction.
A pod that blocks low-frequency traffic noise but lets human speech pass through is not providing speech privacy. It's just a heavy curtain.
Acoustic performance isn't just about keeping sound out. It's also about how the space sounds inside.
A pod with hard, reflective surfaces will feel echoey and uncomfortable — even if it blocks external noise effectively.
Good acoustic design includes：
Absorptive wall panels
Soft furnishings or acoustic ceiling treatment
Carpet or acoustic flooring
Balanced internal reverberation time
The goal： a space that feels calm and comfortable, not like a soundproof box.
Conclusion
Acoustic performance is not a marketing claim. It's an engineering outcome — measurable, testable, and verifiable.
When you evaluate an office pod, don't just look at the number on the brochure. Look for：
✔️ ISO 23351-1 certification with a specific SPLR rating ✔️ Full third-party test reports ✔️ Real-world performance considerations (ventilation, door seals, installation) ✔️ Complementary certifications for safety and air quality
Acoustic performance should be measured — not guessed.
At FlexSpace, we test to ISO 23351-1 and achieve Class A performance (30.1 dB SPLR). We provide full documentation because we believe informed buyers make better decisions.
About FlexSpace
FlexSpace designs and manufactures certified acoustic pods, accessible workspaces, and modular Room-in-Room solutions for modern workplaces. Our products are UL 962 Listed and UL GREENGUARD Certified, with acoustic performance verified under ISO 23351-1.
For spec sheets, test reports, or project consultations, contact us
