Cambria’s own air-monitoring records show silica levels sometimes exceeding federal limits, documents show

(InvestigateTV) — Copies of Cambria’s own air-monitoring records show tests at fabrication shops run by the nation’s largest engineered-stone slab manufacturer repeatedly recorded silica dust above federal limits. That’s despite its chief legal officer’s January testimony to Congress that its shops stay below half the legal limit. The records recently surfaced in litigation and were obtained by InvestigateTV.

Dust from cutting engineered stone countertops — made from crushed quartz bound with resin and containing 90% or more crystalline silica, far higher than granite or marble — has sickened hundreds of workers around the country with silicosis, an incurable lung disease.

In California alone, the state has confirmed 668 silicosis cases and 35 silicosis-related deaths among countertop workers since 2019 as of October 20, according to California Department of Public Health data. Public health experts say cases are undercounted nationally.

Cambria, headquartered in Minnesota, has repeatedly said that smaller fabrication shops around the country need to follow federal regulations and silica dust limits to stay safe, and has held its own facilities out as examples of safely-run shops. But its own testing documents show that on numerous occasions, the company has itself failed to meet federal Occupational Safety and Health Administration safety standards.

Company says safety is a priority

“Safety is a hallmark of the Cambria organization,” Micah Aberson, Cambria’s executive vice president, said in December at the company’s manufacturing facility and fabrication shop in Minnesota. He said eliminating dust while fabricating engineered stone countertops is key to that safety.

“I mean, we would contend that no dust is good dust,” Aberson said.

The dust created by cutting slabs contains respirable crystalline silica. Hundreds of workers who cut and shape countertops around the country have been diagnosed with silicosis. Thirty-five have died in California alone.

At a House subcommittee hearing in January, Cambria’s chief legal officer, Rebecca Shult, said the company keeps workers safe by abiding by federal regulations that set a limit for the amount of silica allowed in the air, known as the permissible exposure limit, or PEL.

“We know that workers can be protected by following OSHA regulations and controlling silica exposure to below the permissible exposure limit. And in fact, at our shops, we control exposures below the action level, which is half of the PEL,” Shult said.

What the thresholds mean

In 2018, OSHA set two thresholds for silica dust in the air. The Action Level, 25 micrograms per cubic meter, triggers closer monitoring of workers. The Permissible Exposure Limit, or PEL, 50 micrograms, is the maximum amount a worker can legally be exposed to in an eight-hour workday.

OSHA also requires medical surveillance when workers are exposed at or above the Action Level for 30 or more days per year.

Shult told Congress Cambria stays under the lower number, half the legal limit, and called for all fabrication shops to do so.

Records show repeated violations

But copies of Cambria’s own air-monitoring records, recently surfaced in litigation and obtained by InvestigateTV, show the company has failed to meet those standards on numerous occasions.

InvestigateTV reviewed Cambria test results from facilities in Minnesota, California, Ohio and Indiana going back to 2018. The tests show Cambria’s own facilities have repeatedly recorded higher levels of breathable crystalline silica in the air than federal rules allow.

Among about 170 tests from 2018 to 2026, 57 — about a third — were at or above the federal Action Level, the threshold Shult told Congress her company stays under. Eight showed more silica than the legal limit itself, the PEL. In Ohio in 2020, one sample came back more than five times the legal limit.

In December, Aberson told InvestigateTV that Cambria does not medically test its own workers for silicosis because, based on its own air monitoring tests, OSHA does not require it.

“We have no evidence of anyone having contracted silicosis at Cambria,” Aberson said. He said Cambria officials “would have heard about it” if any workers had been diagnosed with the disease.

Former OSHA official responds

David Michaels, who served as assistant secretary at OSHA for eight years, testified at the same congressional hearing as Cambria’s chief legal officer, Shult.

“When these stones are cut safely, workers are not overexposed to silica dust,” Shult testified.

After hearing about the test results, Michaels said: “Cambria may insist that it’s possible to do this safely, but certainly from these documents, it does appear that Cambria has not been successful in following essentially that premise.”

Cambria declined to comment for this story.

California moves toward a ban

After hearing from sick workers and their families, California officials have taken the first steps toward banning engineered stone. Public Citizen, a consumer group, joined last month in calling for a ban and a nationwide screening and prevention program for workers.

Australia banned engineered stone in 2024, becoming the first country to do so.