Noise reduction coefficient (NRC), explained
NRC describes how much sound a surface absorbs rather than reflects. It is about what happens to sound inside a space, not about what escapes it, and confusing the two is the single most common mistake people make when reading a specification.
Absorption is not insulation
NRC runs from 0 to 1. A surface at 0 reflects everything, like glass or plasterboard. A surface at 1 absorbs everything, like thick mineral wool. Acoustic ceiling tiles are typically 0.6 to 0.9.
The critical point: absorption controls what a room sounds like from inside. It does almost nothing about what escapes. A pod lined with the most absorbent material available still leaks sound through its door seals if they are poor. Insulation keeps sound in. Absorption stops it bouncing around while it is in there.
Why it still matters in a pod
Because a small box with hard parallel surfaces sounds terrible even when it is acoustically private. Your own voice comes back at you, the microphone picks up the reflections, and everyone on the call hears a bathroom.
That is why the interior lining of a pod matters as much to the experience as the insulation does to the privacy. If the pod is mainly for video calls, this is the specification detail to ask about, and almost nobody does.
Where FocusPod stands
Greater than 29 dB speech level reduction across the range, laboratory tested under ISO 23351-1, measured on the assembled pod with the ventilation running. The accessible model tests at 30 dB, Class A, with reverberation under 0.4 seconds. Test reports are available on request for any model you are specifying.
The rest of the terms
Every acoustic term you will meet in a pod quotation, explained the same way.