The LNG Carrier model is a combination type portable CH4, O2, CO and CO2 gas detector with an Infrared (NDIR) type sensor, galvanic cell type sensor and Electro-chemical cell type sensor. These sensors provide accurate detection of CH4, O2, CO and CO2 levels even in N2 and other inert environemnts. The measuring ranges are 0-100%LEL / 0-100%vol for CH4, 0-25%vol for O2, 0-1000ppm for CO and 0-20.0%vol for CO2 respectively. The RX-515 has an explosion proof and Intrinsically Safe design so that it can be used safely in any environment.