Remote gas monitoring started in the early 1960’s when carbon monoxide detectors were used in Germany to monitor spontaneous combustion activity. These systems were modified and used in the United Kingdom in the late 1960’s to proactively monitor the underground atmosphere; the tube bundle systems we know today. Real time methane detectors and carbon monoxide detectors were used in British Coal in the mid 1980’s. Large mines in Australia can have up to 60 tube bundle monitoring points and up to 200 individual gas sensors underground. This paper discusses the development of these systems as well as potential issues relating to data handling and interpretation.