The minimum amount of fresh air for each employee working underground required by OSHA is which?

The minimum amount of fresh air for each employee working underground required by OSHA is which?

• A. 200 cubic feet per minute
• B. 100 cubic feet per minute
• C. 400 cubic feet per minute
• D. 600 cubic feet per minute

Answer: (A)

Ventilation is about giving every worker a reliable supply of fresh air to breathe and to dilute heat, dust, gases, and other contaminants that can accumulate underground. The minimum required by OSHA is 200 cubic feet per minute per worker. This means each person underground should have at least 200 CFM of fresh air delivered to their breathing zone; if more workers are present, the total ventilation scales accordingly (for two workers, at least 400 CFM, and so on). The goal is to keep oxygen levels safe and contaminants diluted. A value like 100 CFM per person is too low to maintain breathable air or dilute hazards, while 400 or 600 CFM per person exceeds the minimum requirement and isn’t the standard for the basic rule—they might be used in higher-hazard or higher-occupancy situations, but the required minimum is 200 CFM per worker.

Ventilation is about giving every worker a reliable supply of fresh air to breathe and to dilute heat, dust, gases, and other contaminants that can accumulate underground. The minimum required by OSHA is 200 cubic feet per minute per worker. This means each person underground should have at least 200 CFM of fresh air delivered to their breathing zone; if more workers are present, the total ventilation scales accordingly (for two workers, at least 400 CFM, and so on). The goal is to keep oxygen levels safe and contaminants diluted. A value like 100 CFM per person is too low to maintain breathable air or dilute hazards, while 400 or 600 CFM per person exceeds the minimum requirement and isn’t the standard for the basic rule—they might be used in higher-hazard or higher-occupancy situations, but the required minimum is 200 CFM per worker.