A balloon is an inflatable flexible bag
An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflatables depend on the presence of a gas to maintain their...

 filled with a gas
Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...

, such as helium
Helium is the chemical element with atomic number 2 and an atomic weight of 4.002602, which is represented by the symbol He. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table...

, hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

, nitrous oxide
Nitrous oxide
Nitrous oxide, commonly known as laughing gas or sweet air, is a chemical compound with the formula . It is an oxide of nitrogen. At room temperature, it is a colorless non-flammable gas, with a slightly sweet odor and taste. It is used in surgery and dentistry for its anesthetic and analgesic...

, oxygen, or air. Modern balloons can be made from materials such as rubber, latex
Latex is the stable dispersion of polymer microparticles in an aqueous medium. Latexes may be natural or synthetic.Latex as found in nature is a milky fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins,...

, polychloroprene
Neoprene or polychloroprene is a family of synthetic rubbers that are produced by polymerization of chloroprene. Neoprene in general has good chemical stability, and maintains flexibility over a wide temperature range...

, or a nylon
Nylon is a generic designation for a family of synthetic polymers known generically as polyamides, first produced on February 28, 1935, by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station...

 fabric, while some early balloons were made of dried animal bladder
Urinary bladder
The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...

s, such as the pig bladder
Pig bladder
Pig bladder is the bladder of a domestic pig, similar to the human urinary bladder. Today, this hollow organ has various applications in medicine, and in traditional cuisines and customs...

. Some balloons are used for decorative purposes, while others are used for practical purposes such as meteorology
Weather balloon
A weather or sounding balloon is a balloon which carries instruments aloft to send back information on atmospheric pressure, temperature, humidity and wind speed by means of a small, expendable measuring device called a radiosonde...

, medical treatment
Angioplasty is the technique of mechanically widening a narrowed or obstructed blood vessel, the latter typically being a result of atherosclerosis. An empty and collapsed balloon on a guide wire, known as a balloon catheter, is passed into the narrowed locations and then inflated to a fixed size...

, military defense
Barrage balloon
A barrage balloon is a large balloon tethered with metal cables, used to defend against low-level aircraft attack by damaging the aircraft on collision with the cables, or at least making the attacker's approach more difficult. Some versions carried small explosive charges that would be pulled up...

, or transportation
Balloon (aircraft)
A balloon is a type of aircraft that remains aloft due to its buoyancy. A balloon travels by moving with the wind. It is distinct from an airship, which is a buoyant aircraft that can be propelled through the air in a controlled manner....

. A balloon's properties, including its low density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...

 and low cost, have led to a wide range of applications. The inventor of the rubber balloon, (the most common balloon) was Michael Faraday
Michael Faraday
Michael Faraday, FRS was an English chemist and physicist who contributed to the fields of electromagnetism and electrochemistry....

 in 1824, via experiments with various gases.

Decoration or entertainment

Party balloons are mostly made of a natural latex tapped from rubber trees, and can be filled with air, helium, water, or any other suitable liquid or gas. The rubber's elasticity makes the volume adjustable.

Filling the balloon with air can be done with the mouth, a manual or electric inflater (such as a hand pump
A pump is a device used to move fluids, such as liquids, gases or slurries.A pump displaces a volume by physical or mechanical action. Pumps fall into three major groups: direct lift, displacement, and gravity pumps...

), or with a source of compressed gas.

When rubber or plastic balloons are filled with helium so that they float, they typically retain their buoyancy
In physics, buoyancy is a force exerted by a fluid that opposes an object's weight. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus a column of fluid, or an object submerged in the fluid, experiences greater pressure at the bottom of the...

 for only a day or so, sometimes longer. The enclosed helium atom
Helium atom
Helium is an element and the next simplest atom to solve after the hydrogen atom. Helium is composed of two electrons in orbit around a nucleus containing two protons along with either one or two neutrons, depending on the isotope. The hydrogen atom is used extensively to aid in solving the helium...

s escape through small pores in the latex which are larger than the helium atoms. Balloons filled with air usually hold their size and shape much longer, sometimes for up to a week.

Even a perfect rubber balloon eventually loses gas to the outside. The process by which a substance or solute
In chemistry, a solution is a homogeneous mixture composed of only one phase. In such a mixture, a solute is dissolved in another substance, known as a solvent. The solvent does the dissolving.- Types of solutions :...

 migrates from a region of high concentration, through a barrier or membrane, to a region of lower concentration is called diffusion. The inside of balloons can be treated with a special gel (for instance, the polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

 solution sold under the "Hi Float" brand) which coats the inside of the balloon to reduce the helium leakage, thus increasing float time to a week or longer.

Beginning in the late 1970s, some more expensive (and longer-lasting) foil balloons made of thin, unstretchable, less permeable metallised film
Metallised film
Metallised films are polymer films coated with a thin layer of metal, usually aluminium. They offer the glossy metallic appearance of an aluminium foil at a reduced weight and cost...

s started being produced. These balloons have attractive shiny reflective surfaces and are often printed with colour pictures and patterns for gifts and parties. The most important attribute of metallised nylon for balloons is its light weight, increasing buoyancy and its ability to keep the helium gas from escaping for several weeks. Foil balloons have been criticized for interfering with power lines
Electric power transmission
Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...


Professional balloon party decorators use electronic equipment to set the exact amount of helium to fill the balloon. For non-floating balloons air inflaters are used. Professional quality balloons are used, which differ from most retail packet balloons by being larger in size and made from 100% biodegradable latex.

Balloon modelling and balloons in art

Balloon artists are entertainers who twist and tie inflated tubular balloons into sculptures (see balloon modelling
Balloon modelling
Balloon modelling or balloon twisting is the shaping of special modelling balloons into almost any given shape, often a balloon animal. People who create balloon animals and other twisted balloon sculptures are called Twisters, Balloon Benders and Balloon Artists...

). The balloons used for sculpture are made of extra-stretchy rubber so that they can be twisted and tied without bursting. Since the pressure required to inflate a balloon is inversely proportional to the diameter of the balloon, these tiny tubular balloons are extremely hard to inflate initially. A pump is usually used to inflate these balloons.

Decorators may use helium balloons to create balloon sculptures. Usually the round shape of the balloon restricts these to simple arches or walls, but on occasion more ambitious "sculptures" have been attempted. It is also common to use balloons as table decorations for celebratory events. Balloons can sometimes be modeled to form shapes of animals. Table decorations normally appear with three or five balloons on each bouquet. Ribbon is curled and added with a weight to keep the balloons from floating away.

Balloon drops and releases

A decorative use for balloons is in balloon drops. In a balloon drop, a plastic bag or net filled with air-inflated balloons is suspended from a fixed height. Once released, the balloons fall onto their target area below. Balloon drops are commonly performed at New Year's Eve
New Year's Eve
New Year's Eve is observed annually on December 31, the final day of any given year in the Gregorian calendar. In modern societies, New Year's Eve is often celebrated at social gatherings, during which participants dance, eat, consume alcoholic beverages, and watch or light fireworks to mark the...

 celebrations and at political rallies
Demonstration (people)
A demonstration or street protest is action by a mass group or collection of groups of people in favor of a political or other cause; it normally consists of walking in a mass march formation and either beginning with or meeting at a designated endpoint, or rally, to hear speakers.Actions such as...

 and conventions
Convention (meeting)
A convention, in the sense of a meeting, is a gathering of individuals who meet at an arranged place and time in order to discuss or engage in some common interest. The most common conventions are based upon industry, profession, and fandom...

, but may also be performed at celebrations, including graduations and weddings.

For decades, people have also celebrated with balloon release
Balloon release
A balloon release occurs when a number of hydrogen or helium-filled balloons are allowed to float into the sky together, or in rapid succession...

s. This practice has been discouraged by the balloon industry, as it has posed problematic for the environment and cities. In recent years, legislation, such as the California Balloon Law
California Balloon Law
In 1990 the California State Legislature passed SB 1990, enacting a Balloon Law to regulate the sales and use of helium-filled foil balloons. The law was passed in an effort to reduce power outages due to metallized Mylar or foil balloons...

, has been enacted to enforce consumers and retailers to tether helium-filled foil (BoPET) balloons with a balloon weight. This ensures that the helium-filled balloons do not float into the atmosphere, which is both potentially injurious to animals, the environment, and power lines.

At many events, the balloons may contain prizes, and party-goers can pop the balloons to retrieve the items inside.

Balloon publicity

Balloons are used for publicity at major events. Screen printing processes can be used to print designs and company logos onto the balloons. In January 2008, the Jewish Community Relations Council
Jewish Community Relations Council is a generic term for local public affairs organizations which operate under the Jewish Council for Public Affairs umbrella organization.-See also:* Jewish Council for Public Affairs...

 of New York organized a display of 4,200 red balloons outside the United Nations Headquarters
United Nations headquarters
The headquarters of the United Nations is a complex in New York City. The complex has served as the official headquarters of the United Nations since its completion in 1952. It is located in the Turtle Bay neighborhood of Manhattan, on spacious grounds overlooking the East River...


Water balloons

Water balloons are thin, small rubber balloons filled with liquid, usually water, instead of a gas, and intended to be easily broken. They are usually used by children, who throw them at each other, trying to get each other wet, as a game, competition, or practical joke
Practical joke
A practical joke is a mischievous trick played on someone, typically causing the victim to experience embarrassment, indignity, or discomfort. Practical jokes differ from confidence tricks in that the victim finds out, or is let in on the joke, rather than being fooled into handing over money or...

. By forcing water out the open end of a water balloon, it is possible to use it as a makeshift water gun
Water gun
A water gun is a type of toy designed to shoot water. Similar to water balloons, the primary purpose of the toy is to soak another person in a game such as water warfare....


Balloon rockets

Balloons are often deliberately released, creating so called balloon rocket
Balloon rocket
A balloon rocket is a balloon filled with air. Besides being simple toys, balloon rockets are a widely used teaching device to demonstrate physical principles and the functioning of a rocket....

 or rocket balloon. Rocket balloons work because the elastic balloons contract on the air within them, and so when the mouth of the balloon is left open, the gas within the balloon shoots out, and, due to Newton's third law of motion, the balloon is propelled forward. This is the same way that a rocket works.

Flying machines

Large balloons filled with hot air or buoyant gas (often hydrogen or helium) have been used as flying machines since the 18th century. The earliest flights were made with hot air balloon
Hot air balloon
The hot air balloon is the oldest successful human-carrying flight technology. It is in a class of aircraft known as balloon aircraft. On November 21, 1783, in Paris, France, the first untethered manned flight was made by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes in a hot air...

s using air heated with a flame, or hydrogen; later, helium was used. Unlike an airship
An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...

, a balloon travels with the wind.


Angioplasty is the technique of mechanically widening a narrowed or obstructed blood vessel, the latter typically being a result of atherosclerosis. An empty and collapsed balloon on a guide wire, known as a balloon catheter, is passed into the narrowed locations and then inflated to a fixed size...

 is a surgical procedure in which very small balloons are inserted into blocked or partially blocked blood vessel
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...

s near the heart. Once in place, the balloon is inflated to clear or compress arterial plaque
In pathology, an atheroma is an accumulation and swelling in artery walls that is made up of macrophage cells, or debris, that contain lipids , calcium and a variable amount of fibrous connective tissue...

, and to stretch the walls of the vessel, thus preventing myocardial infarction
Myocardial infarction
Myocardial infarction or acute myocardial infarction , commonly known as a heart attack, results from the interruption of blood supply to a part of the heart, causing heart cells to die...

. A small stent
In the technical vocabulary of medicine, a stent is an artificial 'tube' inserted into a natural passage/conduit in the body to prevent, or counteract, a disease-induced, localized flow constriction. The term may also refer to a tube used to temporarily hold such a natural conduit open to allow...

 can be inserted at the angioplasty site to keep the vessel open after the balloon's removal.

Balloon catheter
Balloon catheter
A balloon catheter is a type of "soft" catheter with an inflatable "balloon" at its tip which is used during a catheterization procedure to enlarge a narrow opening or passage within the body...

s are catheter
In medicine, a catheter is a tube that can be inserted into a body cavity, duct, or vessel. Catheters thereby allow drainage, administration of fluids or gases, or access by surgical instruments. The process of inserting a catheter is catheterization...

s that have balloons at their tip to keep them from slipping out. For example, the balloon of a Foley catheter
Foley catheter
A Foley catheter is a flexible tube that is often passed through the urethra and into the bladder. The tube has two separated channels, or lumens, running down its length. One lumen is open at both ends, and allows urine to drain out into a collection bag...

 is inflated when the catheter is inserted into the urinary bladder and secures its position.

Safety and environmental concerns

There has been some environmental concern over metallised nylon balloons, as they do not biodegrade
Biodegradation or biotic degradation or biotic decomposition is the chemical dissolution of materials by bacteria or other biological means...

 or shred as rubber balloons do. Release of these types of balloons into the atmosphere is considered harmful to the environment. This type of balloon can also conduct electricity on its surface and released foil balloons can become entangled in power lines and cause power outages.

Released balloons can land anywhere, including on nature reserve
Nature reserve
A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...

s or other areas where they pose a serious hazard to animals through ingestion or entanglement. Because of the harm to wildlife and the effect of litter on the environment, some jurisdictions even legislate to control mass balloon releases. Legislation proposed in Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

, US, was named after Inky, a pygmy sperm whale
Sperm Whale
The sperm whale, Physeter macrocephalus, is a marine mammal species, order Cetacea, a toothed whale having the largest brain of any animal. The name comes from the milky-white waxy substance, spermaceti, found in the animal's head. The sperm whale is the only living member of genus Physeter...

 who needed six operations after swallowing debris, the largest piece of which was a mylar balloon. To date, there is no documentary evidence to suggest that the death of any sea mammal has been attributed to foil balloons as a sole cause. In the United Kingdom, foil balloons sold at major theme parks and zoos have balloon weights attached to help prevent accidental release into the environment.

Anthony Andrady says that releases of latex balloons that descend into the sea pose a serious ingestion and/or entanglement hazard to marine animals
Marine biology
Marine biology is the scientific study of organisms in the ocean or other marine or brackish bodies of water. Given that in biology many phyla, families and genera have some species that live in the sea and others that live on land, marine biology classifies species based on the environment rather...

 because balloons exposed floating in seawater deteriorate much more slowly than those exposed in air. Balloon manufacturers will often state that a latex balloon is perfectly safe to release into the environment as it is made from a natural substance and will biodegrade over time. However a latex balloon can take up to a year to degrade if it lands in the sea and during this time it is possible for a marine animal to ingest the balloon and die from slow starvation if its digestive system is blocked.

NABAS (National Association of Balloon Artists and Suppliers), a non-profitable organisation that represents the UK balloon industry sets out best practice guidelines to promote balloon safety. NABAS is currently taking on board ISO 14001
ISO 14000
The ISO 14000 environmental management standards exist to help organizations minimize how their operations negatively affect the environment The ISO 14000 environmental management standards exist to help organizations (a) minimize how their operations (processes etc.) negatively affect the...

 to ensure that environmental standards are laid down for the whole UK balloon industry, and to heighten awareness of environmental issues related to balloons. As part of this programme, NABAS has begun discussions with TerraCycle
TerraCycle is a private U.S. small business headquartered in Trenton, New Jersey, which specializes in making consumer products from pre- and post-consumer materials....

 to formulate a feasibility programme for upcycling
Upcycling is the process of converting waste materials or useless products into new materials or products of better quality or a higher environmental value....

 foil balloons into other products.

Air pressure

Once inflated with regular, atmospheric air, the air inside the balloon will have a greater air pressure than the original atmospheric air pressure.

Air pressure, technically, is a measurement of the amount of collisions against a surface at any time. In the case of balloon, it's supposed to measure how many particles at any in any given time space collide with the wall of the balloon and bounce off. However, since this is near impossible to measure, air pressure seems to be easier described as density. The similarity comes from the idea that when there are more molecules in the same space, more of them will be heading towards a collision course with the wall.

The first concept of air pressure within a balloon that is necessary to know is that air pressures "try" to even out. With all the bouncing against the balloon wall (both interior and exterior) there will be a certain amount of expansion/contraction. As air pressure itself is a description of the total forces against an object, each of these forces, on the outside of the balloon, causes the balloon to contract a tiny bit, while the inside forces cause the balloon to expand. With this knowledge, one would immediately assume the a balloon with high air pressure inside would expand based on the high amount of internal forces, and vice versa.

This would make the inside and outside air pressures equal.

However, balloons have a certain elasticity to them that some needs to be taken into account. When you stretch a balloon, you are filling it with potential energy
Potential energy
In physics, potential energy is the energy stored in a body or in a system due to its position in a force field or due to its configuration. The SI unit of measure for energy and work is the Joule...

. When you let it go, the potential energy is turned into kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...

 and the balloon snaps back into its original position (though perhaps a little stretched out).

When you fill up a balloon with air, the balloon is being stretched. While the balloon is constantly releasing kinetic energy in an attempt to contract, it is also being pushed back out by the constant bouncing of the internal air molecules.

Basically, the internal air has to exert force not only to counteract the external air to keep the air pressures "even", but it also has to counteract the natural contraction of the balloon. Therefore, it requires more air pressure (more force) than the air outside the balloon wall.

See also

  • Aerobot
    An aerobot is an aerial robot, usually used in the context of an unmanned space probe or unmanned aerial vehicle.While work has been done since the 1960s on robot "rovers" to explore the Moon and other worlds in the Solar system, such machines have limitations...

  • Balloon-carried light effect
    Balloon-carried light effect
    A balloon-carried light effect is a special effect carried by a balloon, which can be fixed with a rope to the ground or free-flying.-Uses:...

  • Foam balloon
    Foam balloon
    A foam balloon, also known as flogo, is a special type of gas-filled balloon. Strictly speaking a foam balloon is not a balloon, as it has no envelope, but consists of an organic material up-foamed with hydrogen or helium. Thus foam balloons cannot burst. However their carrying capacity is smaller...

  • Pneumatic bladder
  • Radiosonde
    A radiosonde is a unit for use in weather balloons that measures various atmospheric parameters and transmits them to a fixed receiver. Radiosondes may operate at a radio frequency of 403 MHz or 1680 MHz and both types may be adjusted slightly higher or lower as required...

  • Rockoon
    A rockoon is a solid fuel sounding rocket that, rather than being immediately lit while on the ground, is first carried into the upper atmosphere by a gas-filled balloon, then separated from the balloon and automatically ignited...

  • Speech balloon
    Speech balloon
    Speech balloons are a graphic convention used most commonly in comic books, comic strips and cartoons to allow words to be understood as representing the speech or thoughts of a given character in the comic...

  • Two-balloon experiment
    Two-balloon experiment
    The two-balloon experiment is a simple experiment involving interconnected balloons. It is used in physics classes as a demonstration of elasticity....

Further reading

"Reader's Digest
Reader's Digest
Reader's Digest is a general interest family magazine, published ten times annually. Formerly based in Chappaqua, New York, its headquarters is now in New York City. It was founded in 1922, by DeWitt Wallace and Lila Bell Wallace...

: Stories Behind Everyday Things"; New York: Reader's Digest, 1980.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.