For materials used in road construction outside the settlements and the relevant third class Aeff m should not be more than 1500 Bq / kg. There are two classes of radiobezopasnosti. If a specific effective activity has a value of 1500 Bq / kg to 4000 Bq / kg (IV class), make use of material is solved in each case with the federal bodies of Sanitary Inspection. If Aeff m, exceeding 4000 Bq / kg, the materials should not be used in construction. Building- Russian market granite is allowed only with a special certificate. At the same wholesalers who care about their reputation, usually reinsured themselves and take samples purchased the stone. Thus, ability to use granite that do not meet "standards of radiation safety of the population, is virtually eliminated. In addition, these stringent requirements exist only in Russia.
In the U.S. and Europe regulations radioatsionnoy Security is several times lower. And granites, assigned us to the second and even third class are used in homes in many countries, quite fearlessly. In his time building the U.S. market also rocked Wave radiophobia. As a result of a study on the Commission undertook on radiation safety of the President of the United States. The results of this report Professor Donald Langmuir, article "Granite and radon: the problems does not exist ", published in Dimensional Stone.
The main conclusion of U.S. researchers is that the amount of radon emitted from granite cladding to 13,500 times smaller than that of tap water, and 270,000 times smaller than radon in the air outside the home, and therefore can not affect the overall radio background of the room. In this connection it must be admitted that the conversations you have about the radioactivity of natural stones, carry some share of absurdity. Natural radioactivity there billions of years, it is present virtually everywhere. Radioactive materials are included in the composition of the Earth since its inception. And the man himself slightly radioactive – in the tissues the human body one of the main sources of natural radiation are potassium-40 and rubidium-87. What to believe and what materials to give preference, the user selects himself. Want only to recall that many of the alternatives laminated chipboard emit into the atmosphere of phenol-formaldehyde resins, which, like the fumes from plastics used in the production of all other substitutes for granite, causing a much more pronounced injury than negligible radioactivity of natural stones. Article provided by "CAM"