A 2005 WHO report states that smoking using a waterpipe poses a serious potential health hazard and is not a safe alternative to cigarette smoking. The average hookah session typically lasts more than 40 minutes, and consists of 50 to 200 inhalations that each range from 0.15 to 0.50 liters of smoke. In an hour-long smoking session of hookah, users consume about 100 to 200 times the volume of smoke of a cigarette.