What is the maximum allowable CO level for 1996 vehicles during a Smog Check?

The maximum allowable level of carbon monoxide (CO) for 1996 vehicles during a Smog Check is indeed 0.5%. This standard is established to ensure that vehicles meet emissions control requirements, reflecting advancements in emission technology that have been implemented for vehicles produced in that year and onward.

Vehicles from the mid-1990s were designed to operate under more stringent emissions regulations, which is why the allowable CO level is kept relatively low. Monitoring CO emissions is vital as it is a harmful pollutant that contributes to air quality issues and can have adverse health effects. A limit of 0.5% for CO balances emissions reduction while maintaining the operational effectiveness of vehicles from that era.

The other levels presented are not applicable for a 1996 vehicle under California’s Smog Check program, as they either reflect older standards for earlier model years or exceed the current requirements for that timeframe.