3. Results
Data were collected four times (Table 1). The following
measurements were conducted during summer and autumn
2002: (1) before, with worn barrier line, (2) after re-painting
the barrier line and (3) after milling the rumble strip. In addition,
the last measurement was repeated summer 2003 to
evaluate whether the effects were permanent. The final analysed
data included recordings between 13:00–17:00 h for one
day for each measurement.