What is a patch test used for?

A patch test is primarily used to assess the adhesion of an encapsulant coating to a substrate. This is crucial in lead abatement processes, where ensuring that the encapsulant properly bonds to the surface is vital for effective encapsulation and prevention of lead exposure. By applying a small area of the encapsulant to the surface and observing its performance over a specific period, professionals can determine if the coating will adhere effectively under normal conditions.

The other options do not align with the primary purpose of a patch test in the context of lead abatement. For instance, determining paint color compatibility would focus more on aesthetic matching rather than adhesion properties. Testing for chemical resistance pertains to evaluating materials against specific chemicals, which is a different quality concern entirely. Similarly, measuring moisture levels in walls is unrelated to the adhesion performance being assessed by a patch test.