South Korea’s transport ministry has raised the limit of dry ice a plane can carry from 3,300 to 11,000 kilogrammes which will allow more containers of vaccines that need to be stored at ultralow temperatures on each flight.

Deputy minister for civil aviation Kim Sang-do told Reuters the move will triple the number of containers aircraft can carry and allow a Boeing 747 freighter to haul up to 52 containers of vaccines from the usual 15.

Dry ice is typically used by airlines as a cooling material for the transport of pharmaceuticals, which would be the case for some of the Covid-19 vaccines that require ultralow temperatures.

But airplanes can only carry a certain amount of dry ice, or frozen carbon dioxide, as it turns to gas over time and displace the breathable air in the cabin.

Lifting the allowable amount of dry ice would require enhanced safety measures, such as carbon dioxide emission inspection and installation of gas meters, the ministry said in a statement.

Also read: Korean Air Cargo sets up task force to deliver vaccine worldwide

The announcement comes as governments scramble to prepare their cold chain infrastructure to transport temperature-sensitive vaccines.

Pfizer and BioNTech’s vaccine candidate, which needs to be kept below -70℃ and would require dry ice during transport, recently got approval from the UK and Canada. Other vaccine candidates like the one from Moderna require temperature below -20℃.

South Korea on 8 December announced it had ordered Covid-19 vaccines for 88 percent of its population, or 44 million people, with shipments expected to begin no later than March 2021.

Korean Air, on the same day, transported a vaccine ingredient on a flight bound for Amsterdam, which will make its way to a vaccine production plant in Europe, a press release read.

The vaccine ingredient was loaded in special containers that maintain cryogenic temperatures below -60°C and can maintain temperatures below -70℃ without power for 5 days.

A taskforce setup by the airline in September has been preparing for cryogenic temperature transportation of Covid-19 vaccines and reviewing all aspects concerning the vaccine’s transport.

“We are developing a strong system and infrastructure for its safe and swift distribution,” said Eum Jae Dong, senior vice president and head of cargo at Korean Air.

Deputy minister Kim said that a cold storage facility the size of two soccer fields is being built near Incheon Airport (INC) in Seoul, which will be completed in February and operated by Korean Air.