How long for a unit of alcohol to leave the body?

[Routemaster]

Ok so I've heard it takes 1 hour for the average person to process and eliminate 1 unit of alcohol. But does that also include alcohol lost from the body by urinating, sweating, and by exhaling it from the lungs?

Also does percentage Blood alcohol content (BAC) fall if you drink non alcoholic drinks by increasing the volume of blood and decreasing the proportion of alcohol?

 

[price1367]

The guide of 1 unit per hour for an average adult eliminating alcohol includes elimination by all the methods you list, not just your liver.
drinking lots of water will have no effect on you breath alcohol reading.
the likely effect on your blood alcohol reading is complex. Alcohol is a diuretic, it drives alcohol out of your system so you urinate more. Drinking plenty of water does not necessarily increase your blood volume. We have baroreflexes that regulate our blood volume and if they sense that we have enough blood volume then they simply promote the generation of more urine rather than increase the volume of blood.
you can read more about it here:
www.mc.vanderbilt.edu:8080/reporter/index.html?ID=9047
my experience was that people had a "good idea" to get out of being tested or to get a lower reading when drunk...... that usually led to a worse result in the end!