In the present study, student participant irritation levels were erratic while instructor
irritation levels tended to diminish over time, or were absent from beginning to end of the
study (2 instructors reported 0 irritation for all sessions). The instructors’ absent or diminishing irritation over time is consistent with the study conducted by Shiraishi,55 who
reported that with the progression of time, subject irritation levels decreased. Shiraishi55
suspected that individuals become desensitized to FA exposure over time. In the present study, only 1 of 5 instructors ever recorded being irritated at a level above 2.