Sorry for all your delays. Winter travel can be frustrating.

Deicing can be a two-step process.

The first step is the deicing using heated Type I fluid. That removes the snow and ice contamination from the airplane but offers only limited protection for preventing it from reforming.

If the icing conditions continue to exist, a second anti-icing application is made. This is a cold gel-like fluid called Type IV. It can protect the airplane from snow, ice, or frost adhering to the airplane for, depending on the type and severity of the icing, up to several hours. The Type IV fluid is thick and will sit on the airplane until takeoff when it will shear off, from the airflow, taking the snow and ice with it.

Type I is generally pink. It's heated so there's a lot of steam associate with the application. Type IV, green and cold. More like a gel than a liquid.