Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 168; Flight Crew Type 1383
Other / Unknown
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
General None Reported / Taken
Procedure; Weather
When we were in the new deice pad at ORD; we watched an [aircraft] in front of us get deiced. The deice crew used Type 1 on the wings then Type 4 on the wings. They then moved to the fuselage and sprayed Type 1 again. Finally; the tail and sprayed Type 1 then Type 4. I have 2 concerns. Does the overspray of Type 1 onto the already sprayed Type 4 contaminate or dilute the Type 4? Is the time they give for the beginning of the second application accurate?
Air carrier Captain reported concerns regarding de-icing procedures.