Cargo carriers all over the world are loading up aircraft with up to five times as much of a hazardous substance than they would normally be allowed to carry in the name of delivering the Pfizer COVID-19 vaccine. With the recent approvals granted by various governments for use of the vaccine, the race is now on to get it into people’s arms and dry ice, the solid form of carbon dioxide, is key to that effort. The vaccine has to be kept at about -70 degrees Celsius and dry ice is the only widely available material that will maintain that temperature. In a safety alert, the FAA urged caution and awareness in vaccine operations. “In order to transport COVID-19 vaccines, operators may plan to carry dry ice quantities larger than quantities they may carry during typical operations. This volume of dry ice may present risks that existing mitigations do not adequately address.”
The threat is that as the dry ice sublimates, or goes from the solid to the gaseous state, it might overwhelm the ventilation systems on aircraft and threaten the crew. The issue is even more acute on aircraft because the dry ice sublimates faster in lower air pressure. The FAA’s advisory has some timely advice for operators that includes installation of CO2 detectors and ensuring that all air handling systems are in full operating condition before launch. Those systems should be on full blast during ground operations.
Just to be picky, it’s -70 Celsius which is -94 Fahrenheit
Is there a significant weight change during such a flight? How is it calculated?
Yes there is a significant weight change during these flights. From 10,000 to 40,000 pounds of fuel dissipates from the aircraft engines depending on aircraft type and length of flight. Also up to a few hundred pounds of CO2 may be exhausted from the aircraft but that is an insignificant amount for large aircraft. Only a portion of the dry ice actually goes away and only a small portion of the cargo is vaccine with dry ice.
Shalom,
FAA AC-91-76A – Hazard Associated with Sublimation of Solid Carbon Dioxide (Dry Ice) Aboard Aircraft
CAMI Report DOT/FAA/AM-06/19: The Sublimation Rate of Dry Ice Packaged in Commonly Used Quantities by the Air Cargo Industry
Both easily obtainable by internet search….
S
First time I’ve seen convincing argument that excessive CO2 can be harmful.
Don’t let Gretta find out!
The passenger airlines and the cargo carriers have been handling dry ice packages for decades.. Safely..! They have there FAA approved procedures in place and receive annual training.. I believe this is directed to any new comers, ie. charters or small part 135 operators that may find an opportunity to make some cash on the demand..