FIG 4A illustrates {HEAD ~ a normal operating condition} of the elongated conduit body prior to {TAIL ~ the detection} of any ignited flammable gases 
FIG 4A illustrates { HEAD ~ a normal operating condition } of the elongated conduit body prior to { TAIL ~ the detection } of any ignited flammable gases
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH