A joint tester is a specialized device needed to test the integrity of a pipe joint, which is considered to be a structurally weak point sensitive to physical pressure and corrosion. To perform the test, the elements of the joint tester are connected to the pipe joint, creating a sealed space and separating it from the rest of the pipe, thus allowing to test only the joint and disregard the conditions of the connected pipes. If it is an integrity test, water or air is pumped into the joint and the pressure in the cavity is measured. If the pressure declines or fluctuates, the joint is considered fractured and requires repair. Stable pressure indicates that no leaks are present. Joint testers are also able to check the strength of a joint, applying mechanical pressure in different ways to check if the joint is resistant to deformation.