CHICAGO (CBS) — Many Illinois business will re-open their doors Friday morning, and some are scrambling to disinfect every crack and crevice before employees return.

The Morning Insiders wondered what it takes to do a deep clean. CBS 2’s Lauren Victory takes us inside training at a south suburban biohazard company that cleans up crime scenes and more.

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Angela Wang listens close to the scientific explanation of what’s left behind on everything we touch. How much sweat, skin, and more could be on boss Tony Moser’s cell phone? It’s called biofilm and it can trap the COVID-19 virus.

Relative Light Units, or RLUs, are a unit of measuring microbial activity on a surface to determine its cleanliness.

Moser’s phone had 795 RLUs.

“The range we’re looking for is 0 to 60,” he said.

They wipe the prop down and test again; this whole process before disinfecting.

Business at Steri-Clean Illinois is non-stop. Their normal calls for hoarding clean-up disappeared when COVID-19 hit, so Moser marketed around the simple core of his operations: disinfection.

“The first day, I had 42 calls,” Moser said.

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COVID crews are out deep-cleaning workplace after workplace.

“They worked probably over 45 days straight,” Moser said.

It’s why he hired wang. She was laid off from her last job because of COVID.

“I’m glad to be here. I’m happy to help people,” she said.

We asked what has been the most interesting part of her new job, something she didn’t know about it.

“The different chemicals that we work with,” she said. “The dwell times, and all that. I’ve learned a lot.”

Her training is almost complete, which is great timing, because Moser is suiting up to hire two or three more biohazard technicians, just as Illinois businesses are preparing to reopen.

The hoarding jobs also are heating up again.

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The boss’s best advice after a deep-clean? Keep cleaning. Moser said once-a-day wipe-downs are not enough.

Lauren Victory