A fugitive gas pipe supplies {HEAD ~ the fugitive gases} to {TAIL ~ the air intake} and a vent allows the fugitive gases to vent to atmosphere 
to
A fugitive gas pipe supplies { HEAD ~ the fugitive gases } to { TAIL ~ the air intake } and a vent allows the fugitive gases to vent to atmosphere
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH