We want to know whether carbon monoxide (CO) concentrations in a highway tunnel are likely to exceed the US NAAQS standard of 9 ppmv. Important information is as follows (sample data taken from Atmospheric Environment v36, p. 1993-2002): Tunnel dimensions: 7 m high x 12 m wide x 800 m long Ventilation rate: 270 m3 s -1 air leaving tunnel Estimated CO emission factor: 3.6 g CO km-1 vehicle-1 Average traffic load: 1 vehicle every 5 seconds Hint, the timescale for air to leave the tunnel, ?F, can be estimated as Ventilation rate Volume ? F = a) What is the predicted level of CO for the tunnel? b) Do you expect the NAAQS to be violated?