Levels of CO2 under various conditions

The following summarises levels of CO2 under various conditions:
40,000 ppm: The exhaled breath of normal, healthy people.
8,000 ppm: CO2 standard for submarines
2,500 ppm: CO2 level in a small hot crowded bar in the city
2,000 ppm: The point at which my CO2 meter squawks by playing Fur Elise
1,000 to 2,000 ppm: Historical norms for the earth’s atmosphere over the past 550 million years
1,000 to 2,000 ppm: The level of CO2 at which plant growers like to keep their greenhouses
1,000 ppm: Average level in a lecture hall filled with students
600 ppm: CO2 level in my office with me and my husband in it
490 ppm: CO2 level in my office working alone
390 ppm: Current average outdoor level of CO2 in the air
280 ppm: Pre-industrial levels in the air, on the edge of "CO2 famine" for plants
150 ppm: The point below which most plants die of CO2 starvation
(all of these data vary a little with size of the space, ventilation, wind, and the like)

From CO2 data shows nobody's dead from a little carbon dioxide (link)