sec.222Gas monitoring system

### sec.222 Gas monitoring system An underground mine’s safety and health management system must provide for a gas monitoring system complying with this section. The gas monitoring system must provide for the following— continuous monitoring of the mine atmosphere at the return airway of each ventilation split, to detect methane, carbon monoxide, carbon dioxide and oxygen; automatically detecting or calculating the values and trends of the following— gas concentrations; the ratio of carbon monoxide and oxygen deficiency (commonly known as Graham’s ratio); the ratio of carbon monoxide and carbon dioxide; gas explosibility; automatically activating an alarm if a gas alarm level is exceeded; recording the values and trends mentioned in paragraph (b) and displaying the record— at the surface of the mine where the record can be easily accessed by coal mine workers; and in a way that the record can be easily read by the workers; keeping the information on which the values and trends mentioned in paragraph (d) were based at the mine in a way that enables the information to be easily accessed and inspected. The gas monitoring system must also provide for— an alternative electricity supply to ensure the system continues to function if the normal electricity supply fails; and electrical equipment installed and operated underground for the system to have the following explosion protection category— for equipment other than a gas detector head—Ex ia; for a gas detector head—Ex ia or Ex s. (sec.222-ssec.1) An underground mine’s safety and health management system must provide for a gas monitoring system complying with this section. (sec.222-ssec.2) The gas monitoring system must provide for the following— continuous monitoring of the mine atmosphere at the return airway of each ventilation split, to detect methane, carbon monoxide, carbon dioxide and oxygen; automatically detecting or calculating the values and trends of the following— gas concentrations; the ratio of carbon monoxide and oxygen deficiency (commonly known as Graham’s ratio); the ratio of carbon monoxide and carbon dioxide; gas explosibility; automatically activating an alarm if a gas alarm level is exceeded; recording the values and trends mentioned in paragraph (b) and displaying the record— at the surface of the mine where the record can be easily accessed by coal mine workers; and in a way that the record can be easily read by the workers; keeping the information on which the values and trends mentioned in paragraph (d) were based at the mine in a way that enables the information to be easily accessed and inspected. (sec.222-ssec.3) The gas monitoring system must also provide for— an alternative electricity supply to ensure the system continues to function if the normal electricity supply fails; and electrical equipment installed and operated underground for the system to have the following explosion protection category— for equipment other than a gas detector head—Ex ia; for a gas detector head—Ex ia or Ex s. - (a) continuous monitoring of the mine atmosphere at the return airway of each ventilation split, to detect methane, carbon monoxide, carbon dioxide and oxygen; - (b) automatically detecting or calculating the values and trends of the following— (i) gas concentrations; (ii) the ratio of carbon monoxide and oxygen deficiency (commonly known as Graham’s ratio); (iii) the ratio of carbon monoxide and carbon dioxide; (iv) gas explosibility; - (i) gas concentrations; - (ii) the ratio of carbon monoxide and oxygen deficiency (commonly known as Graham’s ratio); - (iii) the ratio of carbon monoxide and carbon dioxide; - (iv) gas explosibility; - (c) automatically activating an alarm if a gas alarm level is exceeded; - (d) recording the values and trends mentioned in paragraph (b) and displaying the record— (i) at the surface of the mine where the record can be easily accessed by coal mine workers; and (ii) in a way that the record can be easily read by the workers; - (i) at the surface of the mine where the record can be easily accessed by coal mine workers; and - (ii) in a way that the record can be easily read by the workers; - (e) keeping the information on which the values and trends mentioned in paragraph (d) were based at the mine in a way that enables the information to be easily accessed and inspected. - (i) gas concentrations; - (ii) the ratio of carbon monoxide and oxygen deficiency (commonly known as Graham’s ratio); - (iii) the ratio of carbon monoxide and carbon dioxide; - (iv) gas explosibility; - (i) at the surface of the mine where the record can be easily accessed by coal mine workers; and - (ii) in a way that the record can be easily read by the workers; - (a) an alternative electricity supply to ensure the system continues to function if the normal electricity supply fails; and - (b) electrical equipment installed and operated underground for the system to have the following explosion protection category— (i) for equipment other than a gas detector head—Ex ia; (ii) for a gas detector head—Ex ia or Ex s. - (i) for equipment other than a gas detector head—Ex ia; - (ii) for a gas detector head—Ex ia or Ex s. - (i) for equipment other than a gas detector head—Ex ia; - (ii) for a gas detector head—Ex ia or Ex s.