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The characteristics of the bong enable the material to be smoked in ways not possible with a simple pipe or spliff. Because the chamber on most bongs can be up to 6 inches (15 cm) in diameter the speed of the air moving through the chamber is reduced and the chamber now acts as a large buffer of smoke. Depending on the length of the bong a considerable amount of smoke can be built up in this way. On the larger bongs, about 4 ft (1.2 m) tall, the operator must stop drawing on the bong when the smoke reaches their lips. At this point the operator must exhale deeply, open the carb, and use the entire contents of their lungs to clear the chamber of the charge of smoke. This high concentration of smoke in the lungs enables the operator to transfer much higher quantities of the chemicals in the smoke into their lungs but also tends to waste large amounts of the smoke. The longer the operator can hold the hit in, the more chemicals he will extract from it, but this becomes more difficult as the smoke gets more dense and the quantity increases. Individuals in the Cannabis culture who can hold in a monster hit are typically held in high regard.

Bubbling the smoke through water also serves to cool down the smoke, which is typically very hot, and to trap some of the heavier and more water-soluble particulate matter, keeping it from entering the smokers lungs. Most smokers believe that bongs are healthier than other smoking devices; however, a 2000 NORML-MAPS study found that waterpipes filter out more psychoactive THC than they do other tars, thereby requiring users to smoke more to reach their desired effect. The analysis used smoke from NIDA-supplied marijuana drawn through a smoking machine adjusted to mimic the puff length of marijuana smokers. The apparatus, comparing smoke from a standard bong, a small portable device with a folding pipestem, a battery-operated model with a motorized paddle to thoroughly mix the smoke in the water, and two different types of vaporizers, found that the unfiltered joint outperformed all devices except the vaporizers, with a ratio of about 1 part cannabinoids to 13 parts tar.