Can this be installed with a sink that does not have an overflow?A. The Hansgrohe 31730 can be installed on any sink you wish. If your sink does not have an overflow, you should purchase a separate drain that does have an overflow.
Can this faucet be installed with a vessel sink that does not have an overflow?A. Unless the faucet is on a riser, it's not recommended for a vessel sink simply because the handles would be very difficult to reach.
Is this faucet CSA approved?A.
Yes, this faucet is CSA approved.