What percent does a person start experiencing blackouts of a bac?

A person typically begins to experience blackouts at a blood alcohol concentration (BAC) of around 0.15% to 0.20%. At this level, cognitive functions and memory formation can be significantly impaired, leading to memory loss or blackouts. However, individual tolerance levels can vary, meaning some may experience blackouts at lower BAC levels. Always drink responsibly and be aware of your limits.