If a driver under 21 years of age is found to have a blood alcohol concentration (BAC) of at least 0.02% but less than 0.08%,

If you are under the age of 21 and a chemical test shows a BAC of at least 0.02% but less than 0.08%, your license will be suspended for 90 days. This is an administrative penalty and the officer can take your license immediately. You may also be required to file proof of financial responsibility (form SR-22) and face criminal penalties. (Note: An average 180-pound man will reach a BAC of 0.03% from the alcohol in just one can of beer before his body starts to break down the alcohol. Hence a legal BAC limit of under 0.02% is effectively zero tolerance.) [Chapter 9: Driving Under the Influence, Nevada Driver's Handbook]