Maximum allowable concentration of CO2 in air for safe working is _____________ ppm (parts per million)?
Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.
A. 50
C. 2000
D. 1000
Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.