A popular trope in detective novels is the “locked room mystery,” in which a murder is committed under seemingly impossible circumstances. The crime scene is a place—a locked room—that no intruder could have entered or left. Only a brilliant, determined detective can solve the mystery.
There’s an analogous situation in medical device manufacturing: How to leak-test an assembly, such as a pacemaker, that is hermetically sealed. With no inlets or outlets, there’s no direct way to get air or a tracer gas into or out of the device. Fortunately, assemblers don’t need Sherlock Holmes to solve this conundrum. They just need to consult an experienced supplier of leak testing technology.