What is the maximum allowable concentration of carbon monoxide during the emissions test for gasoline vehicles?

The maximum allowable concentration of carbon monoxide during the emissions test for gasoline vehicles is 0.5%. This limit is set to ensure that gasoline vehicles meet environmental standards aimed at reducing air pollution and improving air quality. Carbon monoxide is a harmful pollutant that can negatively impact human health and contribute to environmental issues. Therefore, adhering to this threshold helps in the efforts to control emissions and protect both public health and the environment.

Other options present higher levels of carbon monoxide, which would not comply with the regulatory standards that are in place. Maintaining stringent limits, such as 0.5%, reflects the commitment to minimizing the impact of vehicular emissions on air quality.