Intoxication levels depends on the age of the person, the regularity or the amount of alcohol he does every day and obviously on the alcohol user.
An alcohol user could already be intoxicated at a significantly lower Blood Alcohol Concentration of around 0.02 - 0.03 while some require a much higher Blood Alcohol Concentration.
This is again because it varies from person to person and the Blood Alcohol Concentration differs in every person.