From Academic Kids

The stem and bowl in this hand-blown glass bubbler are internal. Compare to the diagram at the left.
The stem and bowl in this hand-blown glass bubbler are internal. Compare to the diagram at the left.

A water pipe or bong is a device used for smoking, usually cannabis (and less frequently tobacco or other substances), in which smoke is bubbled through a chamber containing water. Apocryphal history suggests the term "bong" returned to the U.S. with troops who had served in Vietnam, as a corruption of the Thai word baung, which refers to a hollow pipe or tube.



Principles of operation

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When using a bong, one inhales with his or her mouth sealed over an opening at the top. This reduces the air pressure in the chamber of the bong above the water level in the bottom of the bong. To equalize the pressure, the atmosphere pushes the heated air (from a flame) through the combustible matter in the bowl and down the stem, forming smoke. The smoke then bubbles through the water, into the chamber and into the users' mouth and lungs. This bubbling action leads to a characteristic noise. For example, if you 'bubble' a glass of milk with a drinking straw, by placing the straw beneath the surface of the milk and blowing, you are demonstrating the same physics, except that you are assuming the role of the atmosphere and not the bong user.

Some bongs have a carb, also called a 'shotty' (from shotgun), 'choke,' or 'rush (hole)', a small hole that the user places his finger over when first inhaling allowing the chamber to fill up with smoke. When the user releases the carb while still inhaling, fresh air is allowed to rush in through the hole, "clearing" it of smoke. In other bongs, the bowl-piece is removable. This piece is then called a 'slide' or 'pull', and is similar to the carb in function. When the slide is removed, fresh air instead of smoke bubbles through, and acts to clear the chamber. An audio recording of a bong with a slide style carb being used is available.

Motivations for operation

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.

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The NORML-MAPS smoke analysis apparatus.

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 smoker's 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"[1] ( 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.

Bong water

Used bong water is a notoriously disgusting fluid. In many movies and even in company of others stories are told of bong water's ability to stain anything and make it smell awful. Bong water ranges from clear when it is fresh, to a slightly used green, yellow or brown tint, which will get worse as the water is used more. A common practice of bong users is to turn the bowl around backwards and suck the remaining ash and unburned material down the stem into the water when the bowl is empty. While this is convenient it rapidly degrades the quality of the bong water. If this is done bong water can go from dark green or grey, to black, and will usually have chunks of dark unburned material floating around. As the quality of the water degrades so does the taste of the smoke. Over a long enough time the bong will develop a distinct unpleasant odor and the smoke drawn through it will acquire that taste as well. Bong water is extremely unpleasant to ingest. Drinking bong water will produce minimal psychoactive effect, however, since THC and other cannabinoids are minimally soluble in water.


Since the bong is such a simple device it can be constructed out of nearly anything that is at least semi-rigid and can be made airtight. This includes, but is not limited to bamboo, plastic bottles, apples and oranges, soda-pop cans, buckets, vases, beer bottles, hollow plastic and ceramic statues, chemistry beakers, snorkels, and many other common items. The simplicity of bong construction has led people to consider constructing bongs with materials as outlandish as Pykrete. Most bongs purchased will be made out of glass (either hand blown or cast in molds) or clear acrylic tubing. Most of these bongs will include or otherwise utilize glass stems and bowls. However, cheaper bongs (nearly all made out of acrylic) may be designed with metal stems and bowls.

A common home-built bong is made from a bowl and stem purchased either from a head shop or fabricated from supplies around the house or from a hardware store; this could be out of tinfoil and a short length of garden hose for instance. The rest of the design needs nothing more than a knife or scissors, a 20 oz to 1 liter empty plastic bottle, and some duct tape. Just because a bong can be constructed this way does not indicate it is a good idea; to avoid dangerous fumes and chemicals all bowls and stems should be made of glass or metal.

Using materials such as PVC, plastic, rubber or garden hoses will emit toxic chemicals when heated. Aluminum foil releases toxic chemicals while heated, and its use should be avoided as high aluminum levels have been found in the brains of some patients with neurological diseases. Plastic can release fumes which may induce asthma. Little had been documented on the inhalation of these fumes but it should be avoided. Soda cans are widely used, but it releases aluminum fumes along with paint fumes, which has been shown to cause brain damage. While duct tape may release rubber, metal and aluminum fumes, apples are toxic free.


Offshoots from the simple bong concept do exist. The bucket and waterfall bongs offer the same benefit of delivering a concentrated charge of smoke to the user but are much more effective at making the smoke denser, thence more chemicals can be absorbed. In fact these devices are known for inducing huge coughing fits in their users and can be very unpleasant to use. Regardless, their use is common, especially at parties, as they are extremely effective and can induce fear in people who have never seen them before. Interestingly both the bucket bong and the waterfall bong can be known as gravity bongs and some people using that term may only be familiar with one design.

Bucket bong

This can also be referred to as a gravity bong. See differences and clarifications.

A bucket bong is constructed out of a medium sized bucket filled with water, a two-liter bottle, a bowl, and stem. Anything that can be filled with water and is slightly taller than a two liter bottle can replace the bucket. The device is built by first cutting the bottom off the two-liter bottle (leave as much length as possible). This forms a large dome shape with nearly a two-liter capacity.

Next a hole is cut in the bottle cap and the stem is fed through. The bottle cap is left off for now. Take the plastic bottle and place it in the bucket with the large hole going in first. Submerge the bottle until the water is nearly level with the hole at the top of the bottle. This reduces the capacity of the chamber to nearly zero.

Next the user screws the cap with the bowl onto the plastic bottle, inserts the desired smoking material, lights their lighter, holds the flame to the bowl, and slowly lifts up on the plastic bottle. The user is now creating a large vacuum in the chamber and atmosphere is entering through the bowl and stem. This pulls the heat of the flame with it and ignites the material.

As the user lifts up extremely dense smoke will fill the chamber; the slower the user lifts the denser the smoke will be. This smoke can become so dense that it becomes dark yellow. The user must stop lifting before the bottom of the bottle comes out of the water. Once the height is sufficient the user is ready to ingest the smoke.

The operator unscrews the cap, places their mouth over the opening on top and pushes down on the bottle. The available area is once again decreased, the smoke is forced out the hole at the top, and the user inhales the smoke into their lungs.

Waterfall bong

This can also be referred to as a gravity bong. See differences and clarifications.

Similar in design to the bucket bong is the waterfall bong. A waterfall bong usually consists of a plastic bottle with a hole punched at the bottom and a removable bottle cap with a bowl in it. The bottle cap is removed, the hole is covered by a finger, the vessel is filled with water, then while holding a flame to the bowl, the finger is removed. Gravity causes the water to flow out creating a vacuum inside the chamber and smoke begins to flow into the chamber; see the section on the bucket bong for a more detailed description of this process. When all the water has run out the user removes the bottle cap, places their mouth over the opening at the top of the bottle, and inhales the contents.


A lung is very similar to a bucket bong but instead of using water to provide suction for the bowl a plastic bag taped onto the bottom of a bottle with the bottom cut off. The bag is the sucked into the bottle and then pulled out to provide the suction for the bowl. It is prefered by some as it is more portable than a bucket bong, although is more harsh due to the lack of water (can be placed in a freezer for a few seconds to cool it down).


A bubbler is a small bong that can be operated with only one hand (aside from having to provide an ignition source). In these devices the stem is internal and the bowl is at the very top. A majority of the bong is enclosed with only a hole in the side to act as the carb and the hole the smoke will exit on its way to the operator. These operate very much like a pipe since their internal chamber is so small but they have identical parts to a common bong. Some find them more pleasant to smoke out of than a regular pipe.

Differences and clarifications

Bongs (water pipes)
Bongs (water pipes)
  • Gravity bong and waterfall bong can refer to bongs where there's a flow of smoke induced by a change in air pressure which is caused by the lowering of the level of the surface of the water held within the device.
  • Gravity bong can also refer to a bucket bong even though the water level does not change.
  • When the airflow is caused not by the flux of the water level but by the inhalation of the smoker's lungs, the device is referred to as a hookah, bong, bubbler, or more generally waterpipe.
  • A waterfall or bucket bong, unlike a common bong, does not necessarily filter the smoke through the water or cool it significantly (although they can be constructed to do so). It is simply a device whose main design feature is a large chamber in which the flow of smoke can be condensed, making it easier to inhale a large amount of smoke quite quickly.
  • The erroneously named apple bong is not a bong at all as it does not use a water chamber; rather, it is an improvised device used in lieu of more proper smoking utensils.

Related patents

There are several varieties of US patents on water pipes and bongs.


  • 4,253,475 (,253,475.WKU.&OS=PN/4,253,475&RS=PN/4,253,475) — Water pipes or bongs
  • 4,148,326 (,148,326.WKU.&OS=PN/4,148,326&RS=PN/4,148,326) — Automatic loading bong
  • 4,111,213 (,111,213.WKU.&OS=PN/4,111,213&RS=PN/4,111,213) — Smoking pipe
  • 4,096,868 (,096,868.WKU.&OS=PN/4,096,868&RS=PN/4,096,868) — Smoking apparatus and methods of constructing and utilizing same
  • 4,031,905 (,031,905.WKU.&OS=PN/4,031,905&RS=PN/4,031,905) — Smoking tube with check valve
  • 4,031,904 (,031,904.WKU.&OS=PN/4,031,904&RS=PN/4,031,904) — Removable water tight base for bong
  • 3,863,646 (,863,646.WKU.&OS=PN/3,863,646&RS=PN/3,863,646) — Smoking Device


These include ornamental designs for smoking pipes, substantially as shown and described.

  • D443,950 (,950.WKU.&OS=PN/D443,950&RS=PN/D443,950) — Smoker's implement
  • D443,103 (,103.WKU.&OS=PN/D443,103&RS=PN/D443,103) — Smoker's implement
  • D442,327 (,327.WKU.&OS=PN/D442,327&RS=PN/D442,327) — Smoker's implement
  • D381,116 (,116.WKU.&OS=PN/D381,116&RS=PN/D381,116) — Tobacco water pipe
  • D368,325 (,325.WKU.&OS=PN/D368,325&RS=PN/D368,325) — Tobacco hookah
  • D358,227 (,227.WKU.&OS=PN/D358,227&RS=PN/D358,227) — Tobacco hookah
  • D261,439 (,439.WKU.&OS=PN/D261,439&RS=PN/D261,439) — Pipe
  • D261,438 (,438.WKU.&OS=PN/D261,438&RS=PN/D261,438) — Pipe
  • D256,506 (,506.WKU.&OS=PN/D256,506&RS=PN/D256,506) — Smoking device
  • D246,391 (,391.WKU.&OS=PN/D246,391&RS=PN/D246,391) — Water cooled smoking device
  • D244,473 (,473.WKU.&OS=PN/D244,473&RS=PN/D244,473) — Smoking pipe

See also

External links and references

en:Bong eo:Akvopipo he:באנג sv:Vattenpipa


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