CO2 levels have reached 408 PPM, and the press says people need breathing protection.
If you ride a train, you are inhaling 2,800 PPM CO2.
Your car gets up to 6,000 PPM CO2.
Your house gets up close to 2,500 PPM.
People spend many hours or days at a time indoors at CO2 levels over 1,000 PPM – but if they go outside in 408 PPM apparently they need a gas mask. I’m spending Thanksgiving weekend in Estes Park, where all that excess CO2 is burning the place up.