Editing Silicon dioxide (section)

===Regulation===
Regulations restricting silica exposure 'with respect to the silicosis hazard' specify that they are concerned only with silica, which is both crystalline and dust-forming.<ref>{{cite web|url=https://www.osha.gov/OshDoc/data_General_Facts/crystalline-factsheet.pdf|title=Crystalline Factsheet|access-date=3 August 2017|archive-date=22 December 2017|archive-url=https://web.archive.org/web/20171222125021/https://www.osha.gov/OshDoc/data_General_Facts/crystalline-factsheet.pdf|url-status=dead}}</ref><ref>{{cite web|url=https://www.osha.gov/dsg/topics/silicacrystalline/|access-date=3 August 2017|title=Silica, Crystalline}}</ref><ref>{{cite web|url=http://www.silica-safe.org/ask-a-question/faq|access-date=3 August 2017|title=Frequently Asked Questions}}</ref><ref>{{cite web|url=http://www.ehs.uconn.edu/Word%20Docs/Silica%20fact%20sheet.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://www.ehs.uconn.edu/Word%20Docs/Silica%20fact%20sheet.pdf |archive-date=2022-10-10 |url-status=live|access-date=3 August 2017|title=If It's Silica, It's Not Just Dust!}}</ref><ref>{{cite web|url=http://osha.oregon.gov/OSHAPubs/3301.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://osha.oregon.gov/OSHAPubs/3301.pdf |archive-date=2022-10-10 |url-status=live|access-date=3 August 2017|title=What you should know about crystalline silica, silicosis, and Oregon OSHA silica rules}}</ref><ref>{{cite book|last1=Szymendera|first1=Scott D.|title=Respirable Crystalline Silica in the Workplace: New Occupational Safety and Health Administration (OSHA) Standards|date=January 16, 2018|publisher=Congressional Research Service|location=Washington, DC|url=https://fas.org/sgp/crs/misc/R44476.pdf |archive-url=https://ghostarchive.org/archive/20221010/https://fas.org/sgp/crs/misc/R44476.pdf |archive-date=2022-10-10 |url-status=live|access-date=27 January 2018}}</ref>

In 2013, the U.S. [[Occupational Safety and Health Administration]] reduced the exposure limit to 50 [[micrograms|μg]]/m<sup>3</sup> of air. Prior to 2013, it had allowed 100&nbsp;μg/m<sup>3</sup> and in construction workers even 250&nbsp;μg/m<sup>3</sup>.<ref name=NYT82313 />
In 2013, OSHA also required the "green completion" of fracked wells to reduce exposure to crystalline silica and restrict the exposure limit.<ref name=NYT82313/>