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