What is the allowable ambient concentration of CO in the mine atmosphere under West Virginia law?

The allowable ambient concentration of carbon monoxide (CO) in the mine atmosphere under West Virginia law is set at 35 parts per million (ppm). This standard is established to ensure the safety and health of workers in underground environments where carbon monoxide can be a byproduct of combustion and various other processes.

Maintaining a concentration limit of 35 ppm is critical because CO is a colorless, odorless gas that can be extremely hazardous at higher levels. At this concentration, the risk of acute exposure effects is minimized, thus protecting miners from the potential health risks associated with carbon monoxide inhalation. This limit is based on health research that indicates levels above this can lead to a range of harmful effects, including impaired cognitive function and serious cardiovascular issues.

The values given in the other options either fall below or above the accepted limit and do not align with the legal requirements for mine safety regarding CO concentrations. Thus, 35 ppm is the correct figure for compliance with West Virginia mining regulations.