Footnote — Appendix A16.4: Noise Impact and Significance Criteria



1 DMRB notes in paragraph A2.4 of the noise chapter that perception of changes as small as 1dB(A) after opening may be influenced by factors other than noise: "As this noise change is equivalent to an increase of 25% or a decrease in traffic flow of 20%, this reaction may be partly attributed to an awareness of the changes in traffic rather than noise.".