There are different requirements lavatory faucets (Public vs. private (residential)). We are working on an office building that is not open to the public. The project designer is argueing that this means it is private.

Which is the correct minimum requirement for lavatory faucets? Is it public (i.e. 20% reduction on 1,9l/min) or is it private (i.e. 20% reduction on 8,3 l/min)?