Analysis of the influence of traffic flow variability on noise level on roads

The paper presents the results of analyses concerning the annual variability of the road traffic noise level calculated in the reference point. Because of the large differences between the average noise values and the maximum ones, scaling factors enabling one to convert annual average values into the highest annual averages have been developed. The time range favourable for conducting sampling measurements ensuring the reliable estimation of annual average and highest annual average of the road traffic noise level has been determined. Moreover, factors for scaling the annual average daily traffic (for all vehicles and heavy vehicles, respectively), with a division into two daily periods, have been developed. The scaling factors make it possible to determine the noise level when no direct measurement of traffic intensity can be carried out. The analyses were made using data from 25 automatic traffic recorders (ATRs), equipped with state-of-the-art SICK and Golden river vehicle counters, located on national interurban expressways (class A and S roads).