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1830, Sofia - Buhovo
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In 2021 we celebrate 65 years DIAL.

The history of DIAL Ltd. began to be written in the distant 1956 when the laboratory made its first steps in studying working conditions in the uranium industry and proposing measures to be taken for improvement of the working environment in radiation terms.

The first head of the working group is Dr. Dimov - Military Medicine Doctor - Radiologist. The first measurements for the radiation situation in uranium mining of Bulgaria began. As a result, the first decree of the Council of Ministers introducing the first national norms for work with sources of ionizing radiation emerges.

In 1958, he was founded on a Doximetal Service at Rare Metals Management with Dr. Dimov.

Gradually, the lab employs specialists, and the most appropriate methods of measurement and analysis are implemented. With the help of Russian specialists the work of the laboratory rises to a higher level for a short period of time. This is the first unit for specialized radiation control in the country. At the beginning the major tasks are relatively limited: control of workplaces - radon concentration and external gamma radiation measurement, and rarely measurement of radioactive contamination levels.

In 1960-1961. The MND assigns to the Dosimetric Laboratory, the analysis of all water - potable, waste and technical purposes in all Rare Metals sites in the country, in addition to the radiation control of the working environment.

The facilities and equipment of the laboratory are enriched. Methods for water sample analysis become shorter and more precise. Determination of uranium in water, air and bio-products (organs of deceased miners) are applied by spectrophotometric and pearl luminous methods. Radium is determined in water and air, and polonium in the air of the working environment. Only 3-4 years separate the first exploratory study of the content of long-lived radon daughter products to the implementation of the hidden energy of alpha-decay.

The laboratory perceives this method of assessing the radiation situation only 1 year after Russia, the same year as Czechoslovakia and 2 years before France.

In 1967, research and control of objects outside the Rare Metals system began. Mines such as: Gorubso, Bourgas copper mines, Kremikovtsi, Eliseyna Copper Enrichment Complex and others are being tested.

As a result of these studies and analyzes, the working conditions are considerably improved, measures are taken to limit the radioactive contamination of the mining and workshop air environment and to reduce dust and harmful gases.

In 1979 the  dosimetric laboratory was renamed to the DIAL (Dosimetric and Engineering-Aerological Laboratory) with an order of the General Director of Rare Metals.

Starting as a pioneer in improving working conditions and caring for the environment and human health nationwide, the DIAL continues to develop in this direction to this day.

In 1992, DIAL Ltd. becomes private property with the manager Mladen Mladenov, who manages the company till today.

From the day of the establishment of the laboratory until now, we at DIAL work on a daily and tireless basis to seek and apply increasingly contemporary and modern methods apparatus and equipment to extend the scope of our parameters to provide a cleaner and a healthier environment.

In 2008, under the leadership of Assoc. Prof. Dr. Dobromir Presianov from the Faculty of Physics of the Sofia University (worked in DIAL as a physicist from 1986 to 1991), we built the first anti-Radon shaft in Bulgaria.

In 2017, we successfully completed a project for drawing up a radon map of Bulgaria together with the NCRRD.

Detailed information about the history of DIAL Ltd., illustrated with rich photo material from the archives, can be found in our Jubilee Book, which we published on the occasion of the 50th Anniversary of the Laboratory. The book itself is listed below: