Dry Ice Is Hotter Than Ever

Solid carbon dioxide has long been essential to manufacturing, food processing, and high-school theater. Now it’s a key part of the race to get America vaccinated.

By Charles Fishman

At 4:30 a.m. on the Monday before Thanksgiving, the dry-ice manufacturing floor at Noble Gas Solutions in Albany, New York, was hopping. The machine that compresses carbon-dioxide gas into dry ice was cranking out pellets of the stuff—1,500 pounds an hour—and Noble’s staff was racing to fill hundreds of bags so that a mission-critical product could be distributed on an unforgiving deadline.

“We have a business just 10 minutes down the road that distributes cheesecakes all over the country,” Noble’s vice president of operations, Robert Kohler, told me. After a burst of orders, the company needed more than a ton of dry ice, divided into six-pound bags that could be dropped into shipping boxes alongside the cheesecake, to keep it cold all the way to doorsteps across the country. “They wanted their first delivery at 6 a.m. on Monday. We normally don’t even open until 7 a.m.”

Dry ice often helps save Thanksgiving, even if the beneficiaries of its special magic may not notice. But this winter, it will help save the world from the coronavirus pandemic. A senior salesperson for Noble, which routinely supplies the pharmaceutical industry, had just taken a call from an official with the state of New York, assessing how much dry ice Noble might be able to supply, on short notice, in order to get the first coronavirus vaccine out to every corner of the state once it is approved.

That vaccine, the work of a partnership between Pfizer and BioNTech, is likely to be the first approved by the FDA. It is so delicate that it has to be kept at –70 degrees Celsius (–94 degrees Fahrenheit). That’s not just colder than most freezers; it’s colder than winter at the South Pole. But holding that temperature is not a problem for dry ice, which is a solid at –78 degrees Celsius (–109 degrees Fahrenheit). In fact, for shipping Pfizer’s coronavirus vaccine, nothing else is practical besides dry ice. “There’s really no other way to maintain that temperature stability in transit,” says Azra Behlim, a medical-supply-chain expert at Vizient, a health-care consultancy.

The nation’s dry-ice makers aim to be ready. “We’re getting bombarded with inquiries by hospital districts and public-health departments,” says one employee at a dry-ice supplier, who requested anonymity because he isn’t authorized to speak to the press. Airgas—one of the nation’s largest dry ice companies, with 15 manufacturing sites and 60 distribution centers—is collaborating with the federal government’s vaccine-logistics effort, Operation Warp Speed. “We formed teams to evaluate everything that’s needed throughout the supply chain: How much dry ice might be needed, in different geographies, with different populations. Ensuring the logistics are in place,” says David Joyner, Airgas’s senior director for carbon dioxide. The dry ice planning, says Joyner, is similar to what Airgas did to keep hospitals supplied with medical oxygen during the peak demand in the spring, when the company set up a daily task force to monitor oxygen demand and make sure hospitals got what they needed.

On the other end of the size spectrum are companies like Noble. “We’re currently a one-shift operation,” says Noble’s CEO and owner, Dave Mahoney. “But if the need is there, we can work around the clock if we have to. And if we need to be here around the clock—that’s a good problem to have. It’s just rewarding to know we can be part of the solution to the pandemic.”

Dry ice has long been an indispensable, if mostly invisible, ingredient in the economy. Farmers clean out their wells with it. Cities blast graffiti off walls and statues with it. The nation’s largest meat companies mix it right into their products as they grind them, to keep the temperature safe and the fat from gumming up the grinding equipment. Factories of all kinds—from those that make shoes to those that make frozen waffles—have installed jets of dry ice pellets, right on the manufacturing line, to clean molds in real time.

Dry ice helped remove radioactive debris from helicopters that were used during Japan’s Fukushima Daiichi nuclear disaster in 2011. A company in Utah, Cold Sweep, has perfected using it to lift dirt off the pages and bindings of fragile antique books and manuscripts without harming them. On Broadway, at Halloween parties, and in high-school auditoriums across the country, dry ice makes for convincing theatrical “smoke.”

Dry ice is made by taking purified CO2 gas, chilling it, and pressurizing it to the point that it’s a liquid, then releasing the pressure, which causes the liquid CO2 to take on a snowflake-like consistency. It is then turned into blocks, or into pellets that look like foam shipping peanuts. For cleaning, the dry ice is made into tiny beads the size of rice grains, or smaller. Companies use these like you would use sand-blasting pellets, but once you’ve “dry-ice blasted” a gas turbine, or a mold for making frozen waffles, or the graffiti off a wall, you have no mess to clean up—the dry ice does the cleaning, then simply disappears into the air. Most of the dry ice in the U.S. is made with waste from other kinds of manufacturing—ethanol plants, ammonia and fertilizer factories, and oil refineries produce CO2 as a byproduct, and many capture it to sell to other industrial users. Some of the nation’s biggest dry-ice makers, in fact, colocate their plants adjacent to those facilities, to make using the gas as easy as possible.

“It’s kind of an amazing product,” says Buddy Collen, the general manager for Reliant Dry Ice, which has six dry-ice manufacturing plants across the southern and western U.S. Collen has been in the dry-ice business for 42 years. “It’s really very simple—it’s just carbon dioxide in solid form. That’s it. But there continue to be new applications for it that come along all the time.”

The Pfizer/BioNTech vaccine is on track to win emergency approval around mid-December from the FDA, and if it does, Pfizer has estimated it could provide 25 million vaccine doses, distributed in tiny glass vials, to the U.S. by the end of the year. The vaccine will be distributed in specially designed shipping cases, each a little bigger than a carry-on suitcase, that hold up to 5,000 doses each. Just for the U.S., that’s more than 5,000 cases—and each case requires 50 pounds of dry ice to keep the vaccine inside frozen in transit. Once the cases reach the hospitals or medical centers that will administer the vaccine, they need to be “recharged” with 50 pounds of dry ice every five days, unless the hospital has an ultracold freezer that goes down to –70 degrees Celsius.

The vaccine is itself the product of a taut, complicated supply chain. Raw materials are made in St. Louis. The crucial, and revolutionary, messenger-RNA components are made in Andover, Massachusetts. The elements come together for finishing and packaging at Pfizer’s factory in Kalamazoo, Michigan. All three sites have been working furiously for months making the vaccine, so they would be ready if trials proved it safe and effective. It’s one of the distinctive, and expensive, approaches pharmaceutical companies have taken to this pandemic: producing large quantities of vaccines whose value isn’t yet known, in case they turn out to work. That is why Pfizer (and Moderna, whose vaccine is stable at standard refrigerator temperature) will be able to deliver millions of vaccine doses before the end of the year, starting within days of any approval.

But the dry ice that will make getting the Pfizer vaccine into people’s arms possible can’t be made in advance. Dry ice has many curious qualities, and one of them is that it is devilishly hard to store. As soon as you make it, it starts to disappear.

“Every weekend, I always have one 1,500-pound bin full of dry ice, in stock, for an emergency,” Noble’s Kohler says. “When we come in on Monday, we’ve lost 200 pounds of that 1,500-pound bin.”

Carbon dioxide is never liquid at room temperature and ordinary pressure. Which means dry ice doesn’t melt—it goes directly from being solid back to being a gas, in a process called sublimation. That’s precisely why it is so appealing as a source of “smoke.” It’s also why Kohler’s weekend emergency supply of dry ice, even when stored in an insulated bin, goes from 1,500 pounds to 1,300 pounds over two days.

The sublimation is, to some degree, dangerous—CO2 is heavier than oxygen, to the degree that it carries with it a suffocation hazard. Another node in the great logistical web of America’s vaccine rollout: Shipping companies have to take extra care in flying  large loads of Pfizer’s dry-ice-packed vaccine boxes, so the CO2 doesn’t escape and overcome flight crews. The Federal Aviation Administration has had to give FedEx special guidance to increase their capacity.

Operation Warp Speed has, in the past two weeks, promised to deliver the initial 50 pounds of dry ice to resupply Pfizer’s vaccine cartons to every location that receives the vaccine and doesn’t have a freezer, at the same time as the vaccine itself arrives, via FedEx or UPS.

The vaccine supplies can be stored in Pfizer’s shipping container for another 15 days, if the dry ice is replaced every five days. But if it is to stay frozen, Pfizer says, the box can only be opened twice a day to remove supplies, and then for no more than three minutes each time. The vaccine can be thawed and held at an ordinary refrigerator temperature—2 to 8 degrees Celsius (36 to 46 degrees Fahrenheit)—for five additional days.

So the people who get a container of vaccine will have to plan their need for the vaccine carefully. And because of dry ice’s perishability, once Pfizer’s vaccine is approved, it will set off a furious race to make enough dry ice to ensure the vaccine stays cold as long as it needs to.

Margaret Mary Health is going to need dry ice.

Consisting of a hospital and outlying clinics in four different towns, the system serves a rural area of southeastern Indiana between Cincinnati and Indianapolis, centered in Batesville. The hospital is small, but busy. Last year the ER saw 19,000 patients, and the hospital delivered 500 babies. Before the pandemic, the hospital was licensed for 25 beds, but it’s now allowed to exceed that capacity; earlier this week, it had admitted 30 patients, 13 with COVID-19.

Margaret Mary is one of around 50 hospitals that Indiana has chosen to administer the first round of coronavirus vaccines, which will go to health-care workers. So if the Pfizer vaccine is approved, it will have responsibility for vaccinating hundreds of health-care workers across a five-county region covering 1,400 square miles.

Margaret Mary doesn’t have an ultracold freezer. It also doesn’t have easy access to dry ice—it not only doesn’t use it routinely; it has never bought any. And there isn’t any nearby. In fact, “there are no dry-ice suppliers in the whole five-county region,” Margaret Mary Health CEO Tim Putnam says.

So members of the hospital’s vaccine-planning “strike team,” led by Geralyn Litzinger, the director of community health, have lined up three dry-ice vendors farther afield: two in Indianapolis, 65 miles west, and one in Louisville, Kentucky, 90 miles south.

“We’ve tried to calculate how much vaccine we might get,” Litzinger says, “and how much dry ice we’ll need … We’re making sure we’re set up as customers with those vendors, so we can quickly place orders.”

The dry ice is just one of dozens of details for a small health-care system getting ready to administer the vaccine. Litzinger and her staff are planning to administer the vaccine to health-care workers at two locations across their wide service area, one of which will be a drive-through. Last week, a team from Margaret Mary was at a fire station, testing the Wi-Fi connectivity for the computers the hospital will use to record information about every person who gets the vaccine as they roll through.

Read: ‘No one is listening to us’

In terms of the dry ice and the Pfizer box, Litzinger says, “We won’t open it very often. By scheduling appointments for people to get the vaccine, we should know how many people per day—so when we do access the box, we can pull out only what we need.”

Putnam says the planning at the state level has been as good as could be expected under the circumstances, though the details are always changing. The state has told rural hospitals to ask for help if they can’t secure their own dry-ice supplies.

Meanwhile, America’s dry ice makers will be working overtime to make sure there’s enough dry ice for the first wave of distribution. There was, in fact, a shortage of dry ice in the spring and early summer—Americans were driving less, so ethanol plants were producing less ethanol, and thus less CO2. But the shortage has eased in most places, and many dry-ice suppliers are confident they’ll be able to support the vaccine rollout.

Buddy Collen says that Reliant Dry Ice is keeping a list of health-care outlets that will need dry ice—and waiting for the moment when the vaccine is approved. “We tell them, ‘Call us back when you know what you need,’” he says.

Reliant’s philosophy, Collen says, is that “we have a moral obligation to do everything we can to help make sure these vaccines get to the right places. And we will do everything we can to do that. We also have a responsibility to our existing customers, of course—for some of them, if they don’t get dry ice, they may have to shut down.”

The volumes that most hospitals need—a few hundred pounds a week at most—shouldn’t strain even local dry-ice makers. The greater challenge may be getting dry ice to all those new customers, like Margaret Mary Health, who are far outside the normal distribution channels—either by setting up priority deliveries, or arranging to have hospitals and health departments come collect the dry ice themselves, with all the care transporting it requires.

For a man with 42 years in the business like Collen, the sudden stardom for dry ice is bemusing. “It’s amazing that no one could care less about the dry-ice business until this year,” he says. “It’s always been a quiet business. Now everyone is talking about dry ice.”

This article appeared on The Atlantic website at https://www.theatlantic.com/health/archive/2020/11/pfizer-covid-vaccine-dry-ice-hot/617233/


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