Rapidly acting forms of radiation, which require {HEAD ~ application} for less than about 30 seconds and preferably for {TAIL ~ less than about 5 seconds} are particularly useful 
preferably for
Rapidly acting forms of radiation , which require { HEAD ~ application } for less than about 30 seconds and preferably for { TAIL ~ less than about 5 seconds } are particularly useful
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH