So in continuing the saga regarding traveling with a rebreather in Korea we have received a response back from Incheon Airport. Needless to say still frustrating since it was KAL who stated it wasn’t hazardous (for transport)… (spaces removed for formatting):
This is Security Screening Team at Incheon International Airport Corporation.
As you said, carbon dioxide absorbent is composed of calcium hydroxide.
However because this calcium hydroxide highly corrosive, it is categorized as a dangerous material.
This is why it could not be taken on the plane.
If you are to call your airlines again, you will have to speak to the representative for dangerous materials. When you make the phone call, you will find out calcium hydroxide is a dangerous material.
Security Screening team
Incheon International Airport”
Seems like we will simply have to call to get 100% clarification. It’s not looking good tho…