Pressure Decay leak testing is the most common type of leak testing. The test part is pressurized and the air is allowed to stabilize. After stabilization, the pressure is monitored to determine if the part leaks beyond an allowable amount. Pressure Rise leak testing occurs when the inside of the part is pressurized and the outside of the part is encapsulated inside of a test chamber. The pressure inside the chamber is monitored and if the part leaks, the pressure rises. Vacuum Decay is similar to pressure decay, except the test part is pulled to a vaccuum instead of being pressurized. If the part leaks, air travels into the part to raise the pressure. Water Dunk Tanks are used to lower the part under water. The part is pressurized and if there is a leak, bubbles form on the outside of the part and eventually 'let go' to raise to the water surface. These bubbles can be used to find leaks. The bubbles can also be collected and measured to quantify the leak. High Pressure testing is a specialty which includes many considerations. Safety, special purpose components and temperature control can all be influential factors to the success of this kind of leak testing. Flow Testing detects blockage in channels, ports and tubes. Custom leak test circuits and instruments are available to suit the most unique of applications. Although third party instruments are quite common, sometimes it just doesn't meet the requirements.