Abstract: A monitoring system for leak prevention and leak detection in a pipe line through which a liquid, particularly a petroleum product, passes. The system includes a fitting having two ports. Both ports are connected to an interstitial area surrounding the pipe through which the liquid passes. One port is also connected to a liquid leakage detection device and the other port is connected to a device for preventing liquid leakage to the ambient area.

Abstract: A dual pipe installation comprising a sump including a wall having inner and outer surfaces, and an opening extending there between, a pipe assembly extending into the sump and comprising an outer flexible pipe extending lengthwise and being defined by an endless wall which includes a plurality of corrugations in serially adjacent lengthwise relation, and a lengthwise inwardly open channel, and an inner flexible pipe which extends within the outer pipe, which is defined by an endless wall defining an interior and including a plurality of corrugations in serially adjacent lengthwise relation, and a projecting end portion extending axially outwardly beyond the end of the outer pipe and having an outer end, and which defines, with the outer pipe, an annular space.