Sterile room for application of the film Necessary?

I only bought a times the film because they had reasonably good reviews. They could, however, are expected to arrive at 19:01 already ... I got the mission today, just had to unfortunately admit that the film in no way limited to the phone fits / in every microscopic particle of dust a bubble forms, which is impossible to remove. Cleaning is on the adhesive side of course not possible to give 2 films are unusable. I hope the two new films fold better to me. By the, previously thought lost, films were sent later Here again thanks to Mumbi. However bothers me even the smallest bubble on a slide, which is why I unfortunately had to leave both films after 15 minutes directly in the garbage hiking as unusable.