Zenbooth phone booths, and other phone booth brands, are not 100% soundproof. However, our 3.5" acoustic wall & echo reduction tile technologies dampen noise to the point that conversations had inside of the booths cannot be heard outside.
Since office phone booths are such a new category, there isn't a standardized test for measuring the sound insulation of enclosed spaces like a Zenbooth. Therefore, normal sound rating measurements don't appropriately communicate the function and quality of using a Zenbooth in a noisy office environment.
To test one yourself, make an appointment to see one of our showrooms here.