Noise Change along Traffic Arteries in Chongqing City in 1960-2011

Objective To investigate the change of noise along traffic arteries in Chongqing city and to explore better control measures.

Methods The noise along traffic arteries and the number of vehicles in 10 minutes were tested five times at fixed monitoring sites in 1960-2011.

Results The equivalent sound level (Leq) of noise in day-time at all monitoring sites were higher than the national standard limits, which was 71.3 dB(A). The results of monitoring for 24 h indicated that the noise only in 4:00 AM was lower than the national standard limit, which was 45.8 dB(A). The vehicle flowrate was 21 times more in 2011 than that in 1960, but the change trend of noise was not obvious. The Leq in 2011 was 5.77dB(A) higher than that in 1961 and 0.57dB(A) higher than that in 1997, but the Leq in 2011 was 4.88 dB(A) lower than that in 1983 and 0.68 dB(A) lower than that in 1993.

Conclusions Under the situation of increasing vehicle flowrate, the change trend of noise was not obvious along traffic arteries in the past fifty one years, which indicated that the control measures worked efficaciously.