About the Game

Welcome to the official website of the mobile educational game application "Time Machine: A Quest"!

The game incorporates elements of logic and quest, and consists of the main game (three dimensional game in isometric projection) and several mini-games (two dimensional games) which provide information and certain facts about ozone layer and its depletion. The game is organized around main character (Dr. Bek) and his android instructor (Lola).

Target group: The game is suitable for young and old alike. There are no age restrictions.

Content rating: The game has PEGI 3 content rating.

Technical requirements: A device (smartphone, tablet or PCs with emulators) with Android 4.4 is required for stable work of the game.


Title: "Time Machine: A Quest".

Languages: English and Russian.

Download beta version:


"Time Machine: A Quest" has the following mini-games:

"What is Ozone Layer" mini game, in which it is required to unite correctly the fragments of a paper with important information about ozone layer.

"Expert" mini-game in which it is required that the player enters answers manually. The tasks and questions range from easy ones to difficult ones. It requires using internet and following certain websites. It gives a change to earn additional scores inside of the game. 

"Air-conditioner" mini-game tests knowledge of diverse types substances (refrigerants). The player has to put correctly 4 pairs of substances: ozone-depleting substances, which are no more used; substances with low ozone depleting potential;substances with high global warming potential; ozone-friendly substances with low or zero global warming potential. 

"Ozone Layer History" mini-game checks knolwedge of the history of ozone and ozone layer. The players need to put each historical event  in the correct order.

"Greenhouse gas emissions" mini-game requires to drive a car and reach the end of the distance with minimal level of emissions to the atmosphere.

"Quiz" mini-game challenges the knowledge of ozone and related issues and requires answering correctly to 15 questions by level of difficulty.


Title: "Time Machine: A Quiz" mini-game.

Languages: Armenian, English, French, Portuguese, Russian and Uzbek.




⚬ UNDP/GEF Joint Project "Initial Implementation of Accelerated Hydrochlorofluorocarbons Phase Out in the Countries with Economies in Transition - Uzbekistan"

⚬ State Committee of the Republic of Uzbekistan for Ecology and Environmental Protection | for more information

⚬ UNDP in Uzbekistan | for more information

⚬ UNDP Istanbul Regional Hub | for more information

⚬ Ozone Secretariat, UN Environment || for more information

⚬ OzonAction, UN Environment | for more information


Abror Khodjaev

Akbar Sultanov


Akbar Sultanov


"Circle of Life" and "Eternity" by Martynas Laur


Levon Tumasov


Eldos Fazylbekov


Levon Tumasov


Gustavo Arnizaut - Portuguese language

Jean Paul Martial - French language

Abror Khodjaev - Uzbek language

Akbar Sultanov - Russian language


Paul Newman - NASA

Dan Teng'o - Ozone Secretariat, UN Environment

Anne-Maria Fenner - OzonAction, UN Environment

Halvart Koeppen - OzonAction, UN Environment

Oscar Turner - Tashkent International School


Tina Birmpili - Ozone Secretariat, UN Environment

Shamila Nair-Bedouelle - OzonAction, UN Environment

Selimcan Azizoglu - UNDP Istanbul Regional Hub

Anvar Meliboev - UNDP in Uzbekistan

Rano Baykhanova - UNDP in Uzbekistan

Uktam Utaev - State Committee of the Republic of Uzbekistan for Ecology and Environmental Protection

Ozone Layer


Ozone is present only in small amounts in Earth’s atmosphere. Nevertheless, it is vital to human well-being and ecosystem health. Most ozone resides in the upper part of the atmosphere. This region, called the stratosphere, is more than 10 kilometers (6 miles) above Earth’s surface. There, about 90% of atmospheric ozone is contained in the “ozone layer,” which shields us from harmful ultraviolet radiation from the Sun.

In the mid-1970s, it was discovered that some human-produced chemicals could lead to depletion of the ozone layer. The resulting increase in ultraviolet radiation at Earth’s surface would likely increase the incidences of skin cancer and eye cataracts, and also adversely affect plants, crops, and ocean plankton.

Following the discovery of this environmental issue, researchers sought a better understanding of this threat to the ozone layer. Monitoring stations showed that the abundances of the ozone-depleting substances (ODSs) were steadily increasing in the atmosphere. These trends were linked to growing production and use of chemicals like chloro uorocarbons (CFCs) for refrigeration and air conditioning, foam blowing, and industrial cleaning. Measurements in the laboratory and in the atmosphere characterized the chemical reactions that were involved in ozone destruction. Computer models of the atmosphere employing this information were used to simulate how much ozone depletion was occurring and to predict how much more might occur in the future.

Observations of the ozone layer showed that depletion was indeed occurring. The most severe and most surprising ozone loss was discovered to be recurring in springtime over Antarctica. The loss in this region is commonly called the “ozone hole” because the ozone depletion is so large and localized. A thinning of the ozone layer also has been observed over other regions of the globe, such as the Arctic and northern and southern midlatitudes.

The work of many scientists throughout the world has provided a basis for building a broad and solid scienti c understanding of the ozone depletion process. With this understanding, we know that ozone depletion is indeed occurring and why. Most important, we know that if the most potent ODSs were to continue to be emitted and increase in the atmosphere, the result would be more depletion of the ozone layer.

In response to the prospect of increasing ozone depletion, the governments of the world crafted the 1987 United Nations Montreal Protocol as an international means to address this global issue. As a result of the broad compliance with the Protocol and its Amendments and adjustments and, of great signi cance, industry’s development of “ozone-friendly” substitutes for the now-controlled chemicals, the total global accumulation of ODSs has slowed and begun to decrease. In response, global ozone depletion is no longer increasing, and initial signs of recovery of the ozone layer have been identi ed. With continued compliance, we can expect substantial recovery of the ozone layer by the middle of the 21st century. The day the Montreal Protocol was agreed upon, 16 September, is now celebrated as the International Day for the Preservation of the Ozone Layer.

Why do we care about atmospheric ozone?

Ozone in the stratosphere absorbs a large part of the Sun’s biologically harmful ultraviolet radiation. Stratospheric ozone is considered “good” ozone because of this beneficial role. In contrast, ozone formed at Earth’s surface in excess of natural amounts is considered “bad” ozone because it is harmful to humans, plants, and animals. Natural ozone near the surface and in the lower atmosphere plays an important beneficial role in chemically removing pollutants from the atmosphere.

Stratospheric ozone is considered good for humans and other life forms because it absorbs ultraviolet-B (UV-B) radiation from the Sun . If not absorbed, UV-B radiation would reach Earth’s surface in amounts that are harmful to a variety of life forms. In humans, increased exposure to UV-B radiation increases the risks of skin cancer, cataracts, and a suppressed immune system. UV-B radiation exposure before adulthood and cumulative exposure are both important health risk factors. Excessive UV-B exposure also can damage terrestrial plant life, single-cell organisms, and aquatic ecosystems. Other UV radiation, UV-A, which is not absorbed signi cantly by ozone, causes premature aging of the skin.

In the mid-1970s, it was discovered that gases containing chlorine and bromine atoms released by human activities could cause stratospheric ozone depletion. These gases, referred to as halogen source gases, and as ozone-depleting substances (ODSs), chemically release their chlorine and bromine atoms after they reach the stratosphere. Ozone depletion increases surface UV-B radiation above naturally occurring amounts. International efforts have been successful in protecting the ozone layer through controls on ODS production and consumption.

Ozone near Earth’s surface in excess of natural amounts is considered bad ozone. It is formed by reactions involving human-made pollutant gases. Increasing surface ozone above natural levels is harmful to humans, plants, and other living systems because ozone reacts strongly to destroy or alter many biological molecules. High ozone exposure caused by air pollution reduces crop yields and forest growth. In humans, exposure to high levels of ozone can reduce lung capacity; cause chest pains, throat irritation, and coughing; and worsen pre-existing health conditions related to the heart and lungs. In addition, increases in tropospheric ozone lead to a warming of Earth’s surface because ozone is a greenhouse gas. The negative effects of excess tropospheric ozone contrast sharply with the protection from harmful UV-B radiation afforded by an abundance of stratospheric ozone.

Limiting the emission of certain common pollutants reduces the production of excess ozone in the air surrounding humans, plants, and animals. Natural emissions from the biosphere, mainly from trees, also participate in reactions that produce ozone. Major sources of pollutants include large cities where fossil fuel consumption and industrial activities are greatest. Many programs around the globe have already been successful in reducing or limiting the emission of pollutants that cause production of excess ozone near Earth surface.

In the absence of human activities, ozone would still be present near Earth’s surface and throughout the troposphere and stratosphere because ozone is a natural component of the clean atmosphere. Ozone plays important roles in the atmosphere beyond absorbing UV radiation. 

What are the Vienna Convention and Montreal Protocol

The Vienna Convention for the Protection of the Ozone Layer was adopted in 1985 and entered into force in 1988. Nations that signed the Convention – called the parties – agreed to research and monitor the effects of human activities on the ozone layer and to take concrete action against activities that are likely to have adverse effects on the ozone layer.

The Convention did not require countries to take specific actions to control ozone-depleting substances. The specific actions are spelled out by the Montreal Protocol.

The Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement to protect Earth’s ozone layer by phasing out the consumption and the production of most chemicals that deplete it. The landmark agreement was signed on 16 September 1987 – marked globally as the World Ozone Day - and entered into force in 1989. The Protocol provides a set of practical, actionable tasks to phase out ozone-depleting substances that were universally agreed upon.

The Protocol is unique in having the flexibility to respond to new scientific information. Since its inception the Protocol has successfully met its objectives, and continues to safeguard the ozone layer today

Contact us

If you have comments or suggestions or inquiries please write us to to the following address:

E-mail: game@o3.uz / game@ozonegame.org

When writing please indicate the subject and provide the details.