An air carrier Captain reported it appeared to him that another carrier's de-ice crew was using superior technique to the crew working his aircraft.

Narrative

While we were waiting in line to be deiced; we observed the deice crew deicing and anti-icing the aircraft just ahead of us. When the deice crews began applying Type 4 fluid they were using a straight stream adjustment on their nozzle which was causing a very uneven application of fluid; such that there were small piles of Type 4 fluid on the upper surfaces of the wings and horizontal tail. In addition you could see a very uneven distribution of Type 4 fluid based on a very uneven color (as the fluid is green) on the aircraft surfaces. As we were watching this my First Officer mentioned that directly behind this event we could see [another air carrier] being anti-iced by their deice crew. The [other air carrier]deice crews were using a nozzle angle of approximately 30-45 degrees and sweeping their nozzles back and forth very evenly over the aircraft surfaces which resulted in a very even uniform application of fluid as observed as an even green color over all the wing and tail surfaces. Also [the other air carrier's] deicing crews completed their job much faster and with less than half the fluid used in my opinion. [It appears to me] the [other air carrier] deice crews are applying the Type 4 fluid correctly based on my understanding of the fluid manufacturers guidelines. I believe we should modify the guidance we give to our deice crews to model the technique used by the [other air carrier] deice crews. This change will improve our safety and efficiency in this critical area of our operations.