Matched context for back-flow and escape

The page lists matched contexts for back-flow and escape.

Share - back-flow	Share - escape	Phrase
27.51%	12.57%	prevent {back-flow or escape} [perform operation]
9.86%	4.66%	fluid {back-flow or escape}
6.12%	4.17%	gas {back-flow or escape}
6.55%	2.93%	fuel {back-flow or escape}
18.94%	0.75%	{back-flow or escape} valve
7.24%	1.82%	oil {back-flow or escape}
4.08%	2.31%	air {back-flow or escape}