High-precision leak detection equipment using tracer gas category. Specialized equipment that uses special gases such as helium, hydrogen, and SF6 as detection media, capable of detecting extremely fine leaks (down to 10^-12 Pa·m³/s level). Includes mass spectrometer-type helium leak detectors, hydrogen leak detectors, SF6 leak detectors, and others. Used for sealing inspection of automotive engine parts, refrigeration equipment, semiconductor manufacturing equipment, and medical devices. Unlike pressure decay or bubble testing methods, features high-sensitivity measurement specialized in detecting specific tracer gases. Also covers inspection systems combined with vacuum technology.