Only detectors and chemical analysis can do that. And many hazardous gases, such as methane, have no odor, color, or taste. But keep these properties in mind as we discuss each gas you may encounter in the mine. One or more of these properties may be your first clue that a particular gas is present. This can refer either to what happens when you breathe the gas, or what happens when the gas comes into contact with exposed areas of your body.
Some toxic gases are harmful to inhale.
Other toxic gases harm the skin, or can be absorbed by the skin. As you might guess, an SCBA won t protect you from such gases. If you wear your SCBA in petroleum-based fumes for prolonged or successive periods, the fumes can eventually permeate its rubber parts so that the apparatus no longer provides you with adequate protection. Your team may be forced to leave an area where such gases are detected. Asphyxiating gases cause suffocation.