detect a third number of shock events in {TAIL ~ response} to {HEAD ~ the shock detector} operating at the increased shock threshold; and 
detect a third number of shock events in { TAIL ~ response } to { HEAD ~ the shock detector } operating at the increased shock threshold ; and
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH