Social surveys on community response to a change in aircraft noise exposure before and after the operation of the new terminal building in Hanoi Noi Bai International Airport

A new terminal building in Hanoi Noi Bai International Airport (Vietnam) has been launched since December 2014. After the opening, the number of daily flights increased 1.2 times, resulting in a change in aircraft noise exposure in surrounding areas. Hence, three surveys were conducted around the airport in September 2014, March 2015 and September 2015, respectively.The noise exposures (Lden) were stable between the two first surveys (44, 45 - 66 dB) but increased in the last survey (49 - 69 dB). However, noise levels at particular sites varied considerably among surveys because the runway farther from the terminal buildings was closed for the maintenance till December 2014.Logistic regression analysis was applied to draw the exposure-response relationships for the three surveys. The curve for the second survey is approximately 5% higher than the first survey's while the 3rd survey curve is remarkably steeper than the other two. All the three curves were above and steeper than the EU's. Multiple logistic regression analysis was also applied to the data of the first and second surveys and to those of the second and third surveys. The results showed significant increase in high annoyance between the surveys.