Speech level reduction, and ISO 23351-1
This is the measurement that was written for office pods, as opposed to the ones borrowed from building construction. If you only learn one number in this category, learn this one.
What ISO 23351-1 actually does
The standard is titled acoustics for furniture ensembles, and that phrase is the whole point: it was written for products like pods rather than for walls between rooms.
The assembled pod is placed in a controlled room. A speech-weighted sound source plays inside at a defined level. Microphones measure the level outside at a defined distance. The difference, weighted for speech frequencies, is the speech level reduction, written Ds,2m,nT,w.
Three things make it the right measurement. It tests the whole product, so the door, the seals and the joints are all in the result. It uses speech-shaped sound, because offices are about voices rather than broadband noise. And it is done with the pod working as it would be, ventilation included.
The classes, and what the numbers mean
The standard bands results into classes, and Class A begins at 30 dB. Class B, C and D step down from there in 5 dB bands.
In practice, above about 25 dB a normal conversation inside a pod stops being intelligible in a normal office. Above 30 dB you are into Class A, where even a raised voice is reduced below the surrounding room. Nothing in this category delivers silence, and any supplier promising it is selling a word rather than a number.
FocusPod tests at greater than 29 dB across the range, and at 30 dB, Class A, on the accessible model.
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.