Gas leak detection is a basic checking of gas pipe parts for leak tightness or the presence of leaks. A gas pipe is considered leaktight when there are no gas leaks from the exposed parts. This means that exposed gas pipes in particular are checked for external leak tightness. Leaks are detected by testing a connection point; e.g. at fittings, flanges, screw fittings and gas control valves. It is also important to check gas pipes entering houses and those concealed in cavities at the air outlets. The most up-to-date way to detect gas leaks is to use an electronic gas leak detector (“sniffer”).