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