As a scientist working in Antarctica, I spend most of my time in the lab studying ice. (…) Antarctica is the center of important scientific research, and it must be preserved for this purpose. (…) When tourists groups came here, they take us away from our research. Our work is difficult, and some of our projects can be damaged by such simple mistakes as opening a wrong door or bumping into a small piece of equipment.

Taken from BARTON et al. Northstar. New York: Longman, 2004, p. 22.

According to the text, the word “it”, in line 3, refers to