Hookah

Hookah is a stemmed instrument used for smoking flavored Tobacco. Here, the smoke is passed through a water basin before inhalation. There are some essential components in a Hookah which are mentioned below along with their description.

Bowl is a container which stands as the head of the Hookah and it holds the coal and tobacco during the smoking session. A perforated aluminum foil or screen typically glass or metal covers the bowl. 

A Windscreen covers the bowl area, with some form of air holes. This prevents wind from increasing the burn rate and temperature of the coal. It also prevents ash from being blown onto the surrounding environment. 

Hose refers to a slender flexible tube that allows the smoke to be drawn for a distance, cooling down before inhalation. The end is typically fitted with a metal, wooden, or plastic mouthpiece of different shapes, size, color or material type. 

A Purge valve is connected to the airspace in the water jar to purge stale smoke which has been sitting unused in the jar for too long. The cover should be opened and cleaned of residue and corrosion regularly to ensure proper sealing.

Water jar lies at the bottom of the Hookah. Smoke from the bowl passes through the body and it bubbles through the water. This cools and humidifies the smoke. Liquids such as fruit juice may be added to the water or used in substitution for adding a fruit flavour. 

Plate or ashtray sits just below the bowl to catch ashes falling off the Hookah.

Grommets are usually placed between the body and the water jar. They help to seal the joints between the parts, therefore decreasing the amount of air coming in and maximizing the smoke breathed in.

Diffuser is a piece attached to the bottom of the stem, usually made of plastic, to make a smoother smoke and a subdued noise. This also cools the smoke down more efficiently. It is used as a luxury item for a premium smoking experience and is not a required component.

The bottom jar of the hookah is filled with water. Tobacco is placed inside the bowl at the top of the hookah. Often the bowl is covered with perforated tin foil or a metal screen and coal placed on top. Charcoal used for hookah smoking must be hard, high density, easy to ignite, and burn longer with persistent heat.

When one inhales through the hose, air is pulled through the charcoal and into the bowl holding the tobacco. The hot air, heated by the charcoal vaporizes the tobacco, thus producing smoke, which is passed down through the body tube that extends into the water in the jar. It bubbles up through the water, losing heat, and fills the top part of the jar, to which the hose is attached for inhaling. Stale smoke, if any has to be exhausted through the purge valve before inhaling. 

Smoking the hookah has gained popularity outside of its native Indian region, in Iran, Pakistan and the Middle East, and is gaining popularity in North America, South America, Europe, Australia, Southeast Asia, Tanzania and South Africa.