The roof convergence data for 30 days at a monitoring station in a coal mine gallery is given.
Day
Convergence reading (mm)
0
0
5
4.7
10
11.3
16
19.6
22
28.8
30
34.8
The management decides on a Trigger Action Response Plan (TARP) if the following two premises occur simultaneously. Premise 1: Rate of convergence exceeds 1.5 mm/day between two consecutive measurements. Premise 2: Rate of cumulative increase in convergence exceeds 1.0 mm/day. Identify the day on which TARP is enforced in that gallery.