Development of a Worldwide Aerosol Community – from GAeF to IARA

In former days, research in science and technology was done in defined individual disciplines like physics or chemistry and often limited to the country of origin of the involved researchers. Nowadays, new research areas are often multidisciplinary, international and often transcontinental. This has caused an increasing interest of scientists and researchers in getting information about the ongoing activities around the world and eventually led to building international and interdisciplinary communities. The rise of a new discipline in science and research is usually accompanied by the foundation of corresponding professional organizations in order to promote scientific work in this field, to exchange information by organizing scientific conferences, supporting publications and to establish scientific education and teaching. Relevant markers of the development of associations are the number of members, the composition of the membership, the locations, hosts and participants of conferences, the quantity and main topics of papers presented as well as the language and the proceedings of the conferences.


The Start of International "Multidisciplinary Aerosol Research"
After world war II the industrial activities, for instance mining or steel production, increased in many countries of the world.At the same time, with the growing prosperity, the motorized traffic increased more and more.All these processes increased the emission of gaseous and particulate air pollutants.However, in the beginning only gaseous components like sulfur were considered and successful methods were developed to minimize their emissions.
Gases containing dispersed fine particles are called aerosols.They are more complex in their physical and chemical behavior than just gases or powders, because the behavior of materials in two phases have to be considered.Although the term "aerosol" had been coined by August Schmauss in 1929 to describe the atmosphere as a two-phase system in analogy to hydrosols, it has for a long time mostly been used in medicine for sprayed and inhaled medicines.Around 1970 aerosol research became more directed towards gas-borne particles in and from technical processes like combustion and nuclear safety.In 1990, the nanotechnology including gases with ultrafine particles started making use of the special functional properties of nanostructured materials to develop new products.

Foundation of "Gesellschaft für Aerosolforschung" -GAeF
Aerosol conferences, the so-called "Schwebstofftechnische Arbeitstagung" (conference on suspended matter technology) were held in Germany since 1952.In 1972, a small group of aerosol researchers, who had organized and participated in these conferences, concluded that the further promotion of aerosol science as its own discipline would require the foundation of a new aerosol research association with interdisciplinary and international membership.The "Gesellschaft für Aerosolforschung (GAF, later renamed to GAeF)" was founded as the worldwide first aerosol research association.There might have existed other aerosol groups in the world at that time, but the foundation of GAeF was the nucleus for the formation of a worldwide aerosol community.
Here are some sentences from the announcement by Werner Stöber, the first president of GAeF: "……Purpose of the GAeF is to advance fields of aerosol research in science and technology.With the growing importance of aerosols in various disciplines like biology, medicine, chemistry, physics, technology, meteorology, hygiene and many others, the new association will serve to bring scientists of all aspects of aerosol research together and to provide means of contact for all people in the scientific and technical world who have an interest in aerosol problems.GAeF will make a particular effort to advance the interdisciplinary cooperation in aerosol research.The new association will operate on an international level.…" In a time when the different scientific disciplines acted still very separately, the founding fathers of GAeF obviously recognized that interdisciplinarity is the key to advance aerosol research.This is due to the fact that aerosol science is an applied science comprising many different disciplines.With respect to professional areas, the membership includes scientists and technicians from industry, universities, medical centers and public research institutions.
From the very beginning on, GAeF has had members from many countries around the world, but has been primarily active in German speaking countries.
GAef had a very interesting development of the membership numbers in the beginning (see Fig. 1).
Starting with 38 members in 1972, the membership number steadily increased up to about 150 members at the end of the 1970s.The majority of members during that time period came from Germany and Austria.Between 1980 and 1990 the membership increased drastically.During this time period, the language of the annual GAeF conference has gradually transferred from German to English.In 1982, the conference was held in Bologna (Italy) and thus for the first time outside Germany or Austria.From that meeting on, English was the only conference language.The steep increase in membership in the early 1980s mainly originated from foreign members in Europe and in the USA and less from Germany and Austria, who formed the original nucleus of the association.Three phases of development can be distinguished.In the 1970s GAef was still a mainly German/Austrain association with German as the conference language and conference locations within Germany and Austria.In the 1980s the first international break-through occurred, a situation that was already anticipated in the by-laws and pointed out in the first GAeF announcement after its foundation (see the aforementioned remarks by Stöber).As a result of this opening, the fraction of German-speaking members dropped below 40 %, because of a strong increase of international members.
Towards the end of the 1980's, the slope of the membership development dropped.This time period saw the formation of other European and international aerosol research association, reflecting the European and international vision that GAeF had followed from its beginning.According to the original by-laws from 1972, a main purpose of GAeF has been to organize an annual conference in order to advance information exchange among aerosol scientists in all fields of aerosol research.Until 1987 GAeF organized this annual conference in Germany or Austria (except 1982 in Bologna) with up to 200 participants.Due to the growing number of national European aerosol associations, which all held their own annual meeting, the number of aerosol conferences across Europe had constantly grown.This led to the decision to join forces and organize an annual European-wide conference on aerosol science.The first European Aerosol Conference was held in 1988 in Lund (Sweden).organized by the Department of Nuclear Physics.The European Aerosol Conference is meanwhile very well established in the international aerosol community and is organized by a different European aerosol association in their home country every year.In 1995 the European Aerosol Assembly was founded as an umbrella for the European aerosol research associations.Since then, the EAA is responsible for the planning of the scientific program of the European Aerosol Conference.
Over the time GAeF set up several awards.They were involved in the creation of the Fuchs-Award (see later in the chapter of AAAR and IARA) and set up an award for an honorable person, who played an important role in the organization and activities of GAeF.I got this award in the year 2000.
It was a prosperous coincidence of events that GAeF was founded two years after the start of the Journal of Aerosol

Foundation of "American Association for Aerosol Research" -AAAR
In the early eighties of the last century, GAeF had 152 members.89 (59%) came from Germany and Austria speaking the German language, 33 (22%) from USA.The remaining 28 (19%) were colleagues from European countries as well as 4 Japanese colleagues.The increasing number of Americans started a discussion about the foundation of an American Aerosol Association.
Especially Prof. Benjamin Liu from the University of Minnesota in Minneapolis was supporting the idea and brought it back to the United States.I followed the discussions in the States, because I had spent my postdoc time there.In Minneapolis I learned about aerosols in the atmosphere (smog).I changed my research concept from gas combustion processes down the exhaust pipe to aerosols (air).We established at that time a collaboration with the Particle Lab in Minneapolis and my Aerosol Measurement Technology Division at the new University in Duisburg, Germany.In 1982 David S. Ensor, Sheldon K. Friedlander, Benjamin Y.H. Liu, David T. Shaw and Peter Dietz founded the "American Association for Aerosol Research" -AAAR with international membership.These concerned professionals recognized the importance of aerosols in a number of areas including air pollution, industrial hygiene, atmospheric sciences, clean room technology, and nuclear safety.Their fledgling organization quickly attracted a core group of professionals practicing in these areas.As Secretary General of GAeF (1983GAeF ( -1986) I was also involved in this process and became one of the first foreign members of AAAR.
Today, AAAR is an international organization recognized for its high technical standards and the quality of its Annual Conference.Members include professionals and students from academia, government, and industry throughout the world.Since the foundation they organize annual conferences in different places in the States.Over the years, they have set up a large list of awards, mainly for high quality research.They became involved in the setup of the already mentioned Fuchs Award, together with GAeF and the Japanese Association for Aerosol Science and Technology.
In 2008, the AAAR Board of Directors established a category of Fellow to honor significant contributions by individuals to the discipline of aerosol science and technology, and service to AAAR.AAAR Fellows are expected to actively promote the field of aerosol science and technology and the ideals of AAAR.The AAAR Fellow title will be retained as long as the individual is living.
I was so happy to get this award in 2010.Soon after its foundation AAAR started the journal "Aerosol Science and Technology -AS&T.In contrast to Journal of Aerosol Science it put more emphasis on applied aerosol research.
1986 Foundation of the "International Aerosol Research Assembly" -IARA AAAR and GAeF jointly organized the first International Aerosol Conference (IAC) in Minneapolis in 1984. 2 years later, 1986, the second IAC took place in West-Berlin, Germany. 1983-1986, I was Secretary General of GAeF and therefore involved in the preparation of both conferences.Board members from GAeF and AAAR decided to further internationalize the aerosol community by including the Japanese Association of Aerosol Science and Technology (JAAST) in the preparation of IACs.This resulted in the foundation of the International Aerosol Research Assembly (IARA).The founding members were American Association for Aerosol Research (AAAR), Gesellschaft für Aerosolforschung (GAeF) and the Japan Association for Aerosol Science and Technology (JAAST).The first president was Prof. Kanji Takahashi (JAAST), Prof. Kousaka and I were elected to be the General Secretaries.Four years later in 1990 the third IAC took place in Kyoto, Japan.
The International Aerosol Research Assembly (IARA) is nowadays an assembly of national aerosol research associations from all over the world.IARA`s tasks are to promote scientific knowledge and cooperation in the field of aerosol research internationally, to select a host organization for the international aerosol conference, held every four years, alternating between Asia, North America and Europe, to recognize prominent aerosol scientists with awards supported by all national aerosol associations.
The Fuchs Memorial Award is the premier international prize in aerosol science and is still sponsored by AAAR, the Gesellschaft für Aerosolforschung (GAeF) and the Japan Association of Aerosol Science and Technology (JAAST).Someone called it: "Fuchs Award -the pinnacle of aerosol science".
Presented every four years at the International Aerosol Conference, the award memorializes Nikolai Albertovich Fuchs, the great Russian scientist who is regarded by many as the "father of aerosol science."The award recognizes outstanding worldwide contributions to the field of aerosol research.It is considered the highest honor for researchers in the field.The first Fuchs Award was given to Sheldon Friedlander at the IAC in Kyoto 1990.
IARA also set up an International Aerosol Fellow Award -IAFA.It is granted to recognize outstanding contributions to Aerosol Science and Technology through research, technical development, education and service.
The first award was presented 1990 at the third IAC in Kyoto.The award was given to the cowinners, the first president Kanji Takahashi and the first general secretaries Yasuo Kousaka and me.
David Pui, with whom I worked together many times (see chapter Commemorative Session) and I felt a couple of years ago that international collaboration should be more honored and supported.We arranged the "Fissan-Pui-TSI Award" fund.This award is granted by the International Aerosol Research Assembly (IARA) to recognize international collaboration in the field of aerosol science and technology between researchers/engineers residing on at least two different continents.This endowment fund was established in 2005 with a $75,000 donation from TSI Incorporated, which provided the award amount in 2006 and $65,000 to support future awards.It is presented every four years at the International Aerosol Conference like the Fuchs Award.

Foundation of the "European Aerosol Assembly" -EAA
Over the years, many national aerosol associations were formed in Europe and in Asia.Several of them started to organize their own annual conferences, which caused a kind of competition between the national associations.In Europe 1988 the annual GAeF -Conference was named European Aerosol Conference -EAC.It has since then been organized by another national association in its country every year and supported by all European Aerosol Associations.
During my GAeF presidency (1991-1994) I felt there is the need for an assembly which includes all aerosol associations in Europe to be a comparable competitor to AAAR.I described it in an announcement: "Among others, one of the tasks of the GAeF Board is to get together some kind of "European Aerosol Assembly -EAA" which combines and supports the interest of all national aerosol societies in Europe".
Beside the competion with America, our interest was also to include already existing associations from eastern countries once they form."I heartly invite colleagues from eastern countries to take part in the discussion".(This interest in eastern countries was mainly due to the German reunion in 1990.) Several board members of the European Aerosol Associations agreed upon the listed goals for the Assembly: The European Aerosol Assembly (EAA) aims at: • providing a forum for co-operation between National Aerosol Societies • establishing a common policy on the running of the European Aerosol Conference In the meantime, the award has been replaced by the EAA-Award, which is intended to recognize outstanding performance of an individual whose career has been distinguished by a sustained commitment to excellence in endeavors of science, research, and leadership in the field of aerosol science and technology.Preference therefore should be given to a senior individual, in recognition of their complete scientific life.The award is given bi-annually and presented during the European or International Aerosol Conference.
Of course all EAA-Member Associations can present their own awards at the EAC.Through EAA, the Journal of Aerosol Science (JAS) became the accepted journal of all European Societies.

Asian Aerosol Research Assembly -AARA
The first aerosol association in Asia was the "Japan Association of Aerosol Science and Technology -(JAAST).Members of this association attended the second International Aerosol Conference in Berlin, co-organized by GAeF and AAAR in 1986.Besides JAAST further aerosol research associations were founded in Asia in the following years.
One of them is the Taiwan Association for Aerosol Research (TAAR).The importance of aerosol science and technology in Taiwan was recognized around 1990, when Taiwanese scholars including Prof. Chiu-sen Wang, Prof. I-Fu Hung, Prof. Man-Ting Cheng, Prof. Chuen-Jinn Tsai, colleagues of ILOSH (Institute of Labor, Occupational Safety and Health, Taiwan) and many others had decided to form an aerosol association that is devoted to foster aerosol science and technology research in their country.The Chinese Association for Aerosol Research in Taiwan (CAART) was finally founded in August 1992 which was later renamed as Taiwan Association for Aerosol Research (TAAR) in August 2007.Its mission is to promote research and applications of aerosol science and technology in Taiwan.TAAR started the annual International Conference on Aerosol Science and Technology (ICAST), which has been well attended since then.
In 2001, the Asian Aerosol Research Assembly was founded.The reasoning and the concept of the Asian Aerosol Research Assembly (AARA) are very comparable as for EAA.
The founding associations were: AARA took over the responsibility of the Asian Aerosol Conference (AAC).It had started already in Nagoya, Japan in 1999 and is held bi-annually.The 12 th Asian Aerosol Conference was held in Taiwan in 2022.It is one of the premier events for Asian researchers and professionals in aerosol science and engineering.
The Asian Aerosol Research Assembly (AARA) has established the AARA-Fellows to recognize individuals with outstanding service to the AARA and significant contributions to the field of aerosol science and technology in Asia for more than 10 years.Up to 2 individuals are appointed AARA-Fellows once every two years.
The Asian Young Aerosol Scientist Award was established by the AARA and TSI Incorporated to recognize young scientists from Asia, Australia and New Zealand, who have made outstanding contributions in aerosol science.
Since 2001, TAAR started to publish the journal Aerosol and Air Quality Research (AAQR), which was later turned into a SCI journal in 2008.Nowadays, AAQR publishes 12 issues (200+ articles) per year focusing on all aspects of aerosol science and technology, atmospheric science and air quality related issues.
Aerosol and Air Quality Research (AAQR) is dedicated to serve the worldwide scientific community through publication of high-quality and high-impact scholarly, multi-and inter-disciplinary research that broadly resides in the fields of aerosol and air quality.AAQR is committed to provide a platform that disseminates scholarly work, findings and knowledge promptly, openly and freely to all, and thus promote academic and public discussion and communication.By this, AAQR strives to be one of the leading aerosol and air quality journals in Asia and the world.

The Status of the Worldwide International Aerosol Research Community
A successful interdisciplinary aerosol research and science needs international collaboration and communication.Therefore, national associations have to be combined and form an assembly.Finally, the assemblies may be members of an overarching assembly, which is responsible for worldwide activities of the aerosol community (see Fig. 2).
Aerosol researchers decided to form the assemblies on a regional basis.The AAAR is responsible for the USA and neighboring countries.I am calling AAAR an aerosol research assembly, because it is covering a large part of the world and the aerosol research activities in the United States are manifold and important.Europe is presented by EAA and AARA is active in Asia.associations, which are members of the assemblies.AAAR is only one, EAA has 15 and AARA 7.
IARA is representing all participating associations over the world.The total number of associations combined in regional assemblies is 23.It is difficult to determine the total worldwide number of personal members of all aerosol associations, because of the allowed and wanted multiple membership.
Aerosol researchers should not only support national associations, but also work within the assemblies.Besides excellent conferences, it is also important to create more assembly awards.Since the assemblies are the institutions in which creation of collaboration is the major goal, friendship is also an important task.
I believe, science is more than just gaining and generating knowledge.It has also a social component, which is international cooperation and collaboration, which a community needs to be effective.Othmar Preining pointed this out in his opening address of the tenth GAeF conference in 1982, in which -looking back over the past ten years-he pointed out that all these conferences have been "meetings of a family, from many countries around the world, not only scientifically rewarding but also very important for their human aspects."(J. Aerosol Sci. 14: 179, 1983) The main task for the members is to support the activities of the associations and assemblies they belong to and to create collaboration.The best way to achieve this is international friendship among the members.A good example is a friendship club like the one founded by David Pui (US), Yasuo Kousaka (Japan), Michel Pourprix (France) and myself (Germany).This is described in more detail in the commemorative articles for David Pui's work over the last 50 years.
I try to push the further development of worldwide aerosol community, which leads in the actual situation at least to peace between aerosol researchers.
Science (JAS) by C. N. Davies from England.Leading GAeF members soon came into close contact with the new journal, and it became a quasi-official journal of GAeF.The rights of the journal were in the meantime completely transferred to Elsevier as the new publisher.With the increasing pursuit of establishing a culture of open access publishing, plans for establishing a new, full open access aerosol journal under the umbrella of the European Aerosol Assembly are currently underway.
• coordinating the timetable of national meetings • acting as the point of contact for non-European organizations • facilitating the flow of information between the European societies • encouraging the development of education in the field of aerosol science • assisting the formation of specialist working groups • acting as a focus in lobbying the E.U. and other funding bodies to encourage the growth of research in the field of aerosol science and technology 1995 the EAA was founded at the EAC in Helsinki.In the beginning the EAA was composed of representatives from 6 d`Etudes et Recherches sur les Aérosols France The European Aerosol Assembly (EAA) is the umbrella over all national and regional aerosol research associations in Europe with the goal to strengthen transnational endeavors and collaborations and to organize the scientific program of the European Aerosol Conference.EAC became a true European conference of high quality due to a Europeanwide program of working groups.Five working groups are currently active inside EAA, covering the full breadth of aerosol science: -WG 1: Aerosol Technology -WG 2: Atmospheric Aerosol Studies -WG 3: Aerosol Measurement Techniques -WG 4: Aerosols and Health -WG 5: Basic Aerosol Processes The EAA introduced the Junge Award in 2003.It was intended to recognize the outstanding research contributions of a senior individual, who has shaped a completely new field of aerosol science and/or technoIogy.The first winner of the award was Sheldon Friedlaender.I got this award in 2005 at the EAC in Madrid.
Chinese Society of Particuology (CSP) • Clean Air Society of Australia and New Zealand (CASANZ) • Indian Aerosol Science and Technology Association (IASTA) • Japan Association of Aerosol Science and Technology (JAAST) • Korean Association for Particle and Aerosol Research (KAPAR) • Taiwan Association for Aerosol Research (TAAR) • Thai Powder Technology Center (TPTC)

Fig. 3 .
Fig.3.The structure of the aerosol community worldwide, countries with participating associations, the regional assemblies AAAR, EAA and AARA and the combining International Aerosol Research Assembly (IARA).