Even for personnel in granite quarries or refineries and production sites there is no indication of risk through radiation from Radon. That is the conclusion of two studies commissioned by the Marble Institute of America (MIA).
Thus there is no distinction in risk between craftsmen and workers or landlords and tenants of dwellings with granite kitchen counter-tops or other stone fixtures.
The studies were carried out by the Environmental Health & Engineering in Cambridge, Massachusetts. The studies have meanwhile been published in the Journal of Radiological Protection and reviewed by distinguished members of the scientific community.
Sample measurements in US-State of Vermont’s granite quarries showed that the radioactivity reached levels below 0,3 Picocurie pro Liter (pCi/L), even under worst case scenarios. This observed value is less than the average natural background radiation in the United States.
Safety levels were similarly inoffensive for refinement of granite e.g. when workers breathed in stone-dust, with levels well below the allowed safety-levels according to a MIA press-release.
Radon is emitted constantly from the Earth crust as a product of Uranium and Thorium decay. In the atmosphere the gas is dissipated making it the element with the lowest atmospheric concentration. But in closed basements the gas can reach concentrations similar to those found in Uranium mines. The inert gas is radioactive and can cause lung cancer.
The studies were commissioned in light of the impending examinations by the U.S. Environmental Protection Agency (EPA) on the subject of on the job safety. Since there were no reliable statistics available MIA took the bull by the horns.
The statistics to the studies and the history behind them are published on a MIA web-site.
The research was funded through generous contributions by MIA members to the Truth About Granite Fund. Additional contributions were made by the Building Stone Institute, Elberton Granite Association, Indiana Limestone Institute, the National Tile Contractor’s Association, the Mason Contractors Association of America, and the National Building Granite Quarriers Association.
(23.05.2014, USA: 05.23.2014)