EPA Said to Tighten Soot Rules That Industry Sought to Weaken

EPA Said to Tighten Soot Rules That Industry Sought to Weaken

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The annual standards for particulate matter, or microscopic particles released from automobile exhausts, power plants or factories, will be set at 12 micrograms per cubic meter, down from 15 micrograms now, according to the person who asked not to be named before the agency’s public announcement.