What component is crucial for a press joint to be labeled as compliant?

A fitting manufacturer approved tool is crucial for a press joint to be labeled as compliant because it ensures that the connection is made to the specifications set forth by the manufacturer. These tools are designed to apply the correct amount of force necessary to create a secure and leak-tight joint, which is essential for the integrity of the plumbing or mechanical system. Using a tool that is not approved by the manufacturer may compromise the joint, leading to potential failures or leaks, and could also void any warranties associated with the fittings. Therefore, compliance is directly tied to the use of the specified installation tools, which are engineered to work specifically with the materials and design of the fittings in question.