An imaging scope includes an internal surface defining an internal cavity, a window permitting visual inspection of the internal cavity, a fluid in the internal cavity having a pressure different than ambient pressure, and a leak indicator transitionable between nonvisible and visible through the window when the pressure of the fluid changes toward ambient pressure.

Methods and apparatus for checking emitter bonds in an irrigation drip line and for manufacturing drip line in a manner that allows the bond between the in-line emitter and surrounding conduit to be checked. In one form, a downstream in-line vacuum tester is provided for monitoring the amount of air escaping from outlet openings in the drip line to detect excessive air associated with poorly bonded emitters.

Methods and apparatus for checking emitter bonds in an irrigation drip line and for manufacturing drip line in a manner that allows the bond between the in-line emitter and surrounding conduit to be checked. In one form, a downstream in-line vacuum tester is provided for monitoring the amount of air escaping from outlet openings in the drip line to detect excessive air associated with poorly bonded emitters.

Methods and apparatus for checking emitter bonds in an irrigation drip line and for manufacturing drip line in a manner that allows the bond between the in-line emitter and surrounding conduit to be checked. In one form, a downstream in-line vacuum tester is provided for monitoring the amount of air escaping from outlet openings in the drip line to detect excessive air associated with poorly bonded emitters.

Methods and apparatus for checking emitter bonds in an irrigation drip line and for manufacturing drip line in a manner that allows the bond between the in-line emitter and surrounding conduit to be checked. In one form, a downstream in-line vacuum tester is provided for monitoring the amount of air escaping from outlet openings in the drip line to detect excessive air associated with poorly bonded emitters.

There is provided a method of detecting a leakage of a substrate holder in an apparatus for plating. The method of detecting the leakage comprises: placing the substrate holder that holds a substrate, into a tank that is filled with a liquid; supplying a gas into an internal space of the substrate holder that seals an outer circumferential portion of the substrate; and taking an image of the liquid surrounding the substrate holder in a state that the internal space of the substrate holder is pressurized by the gas and analyzing one or a plurality of taken images to determine presence or absence of gas bubbles in the liquid and thereby detect a leakage of the substrate holder.

There is provided a method of detecting a leakage of a substrate holder in an apparatus for plating. The method of detecting the leakage comprises: placing the substrate holder that holds a substrate, into a tank that is filled with a liquid; supplying a gas into an internal space of the substrate holder that seals an outer circumferential portion of the substrate; and taking an image of the liquid surrounding the substrate holder in a state that the internal space of the substrate holder is pressurized by the gas and analyzing one or a plurality of taken images to determine presence or absence of gas bubbles in the liquid and thereby detect a leakage of the substrate holder.

A method for manufacturing a leak tight porous component includes the steps of forming a porous component; applying a first application of a surface sealant layer to the component; providing pressurized gas into a wall of the component via a known leak in the surface sealant; applying liquid to the component while pressurized gas is flowing into the wall of the component via the known leak. The method further includes the steps of inspecting the component for the formation of bubbles; identifying a new leak area in the component; removing at least a substantial amount of liquid from the component; and applying a second application of surface sealant to the new leak area.

A method for manufacturing a leak tight porous component includes the steps of forming a porous component; applying a first application of a surface sealant layer to the component; providing pressurized gas into a wall of the component via a known leak in the surface sealant; applying liquid to the component while pressurized gas is flowing into the wall of the component via the known leak. The method further includes the steps of inspecting the component for the formation of bubbles; identifying a new leak area in the component; removing at least a substantial amount of liquid from the component; and applying a second application of surface sealant to the new leak area.

A method of testing for leakage of a pulp chamber in a modified extracted tooth is provided, wherein the modified extracted tooth comprises enamel, dentine and a pulp chamber. The method comprises: (a) providing an extracted tooth which has been modified by removal of roots and dental pulp so as to create a pulp chamber, the pulp chamber having an opening at one end thereof, which opening is defined by a rim; (b) attaching a first end of a first tube to the rim of the pulp chamber so as to provide an air-tight seal between the first tube and the rim; (c) placing the modified extracted tooth into a liquid; (d) supplying a compressed gas into the pulp chamber via the first tube; and (e) determining visually whether or not bubbles of the gas are released into the liquid at the enamel of the tooth.