Abstract
The author reports the results of carbon monoxide measurements carried out in Berlin from 1965 to 1971. At the road side with heavy traffic the maximum half-hour average value was 61 p. p. m., while the maximum daily average value was 32 p. p. m. In tunnels the measured CO content was over 100 p. p. m., which is actually the half-hour average value. At a measuring station far from road traffic the CO concentration increased with 20 p. p. m. in 10 hours as a result of steady weather condition. On lakes and rivers with heavy motor boat traffic a maximum half-hour average value of 10 p. p. m. was reached.