Can Blow to Know be customized to measure the legal drinking / blood alcohol content (BAC) limit of each state?
Yes, each machine can be manually set (and reset) to accommodate any BAC level.

How long is it necessary to wait between tests to have a reliable result?
2 minutes.

Why shouldn't I smoke or drink 10 minutes before the test?
Chemicals and residue in the mouth from recent drinking and smoking can significantly impact the test results.

What happens if someone blows some liquid into Blow to Know when the test is being done?
Nothing happens. The machine has a liquid outlet system.