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Where I work we manufacture products from granite and other natural materials. Should I be concerned about radiation in my workplace?

I work in a granite fabricating and finishing shop. Is there a radon risk in my workplace?

Based on existing studies, most types of granite used in countertops and other aspects of home construction are not typically known to be major contributors of radiation and radon in the average home. To date, the Occupational Safety and Health Administration ("OSHA") has not performed any testing for radon in the workplace where granite is fabricated or finished. However, because some granites are more radioactive than others, depending on the composition of the molten rock from which they formed, it is possible that radon is present in your workplace at levels exceeding background radon concentrations. The only way to know for sure is for your employer to test your workplace. The OSHA method for measuring radon gas concentration is briefly described at "Chemical Sampling Information: Radon," available at A more detailed technical description is given at "Radon in Workplace Atmospheres, The OSHA Ionizing Radiation Regulations" available at EPA also provides information about radon testing.

Is exposure to radon in the workplace from granite and other natural materials regulated?

Yes. Radon is a naturally occurring radioactive gas that is covered by the OSHA standard for ionizing radiation exposure in the workplace. As described in "Radon in Workplace Atmospheres," the OSHA radon exposure limit for adult employees is 100 pCi/L averaged over a 40-hour workweek. The OSHA standard also requires employers to survey the workplace as necessary. Such evaluation includes a physical survey of the location of materials and equipment, and measurements of levels of radiation or concentrations of radioactive material present. The OSHA standard for ionizing radiation can be found at

Who should I contact if I have questions about radiation in the workplace?

OSHA maintains a safety and health topics page that contains useful information at Or, you can call 1-800-321-OSHA. Operators can help you with your questions and direct you to an OSHA office or state program in your area.