The Morrison Fig. 346 Series External Emergency Valve is for installation at the outlet of an AST or in a liquid transfer line where product fl ow must be stopped in the event of a fi re. Fig. 346 flanged external emergency valves conform to ANSI B16.42 specifications for class 150 raised face ductile iron flanges. Cold non- shock pressure rating is 200 P.S.I. W.O.G. for sizes 1.5", 2", 3" and 250 P.S.I. W.O.G. for the 4". Ductile iron valves are painted green and stainless steel valves are painted blue for designation purposes.