In the session 2 discussion, Professor Rylander asked about the possibility of comparing results from railway noise studies done in different countries. He said that data he had examined relating to aircraft noise (Scandinavia, France and Japan) and traffic noise (Sweden and Italy) showed similar noise level-annoyance level relationships, thus suggesting that comparisons are feasible with existing data. Dr Fields answered that many variables might lead to non-comparable results, among them the method of measuring and summarizing noise. Dr Langdon said that though it is interesting to compare studies, reasonably precise predictions of the relationship are needed for useful comparisons. Dr Fields stated that annoyance is a meaningful measure of human response even if it is complicated and affected by many factors other than the noise level. The measurement of this response can be affected by the design of investigations generally and questionnaire items in particular.
Dr King said he did not like the interview technique and suggested that complaints should be used as a measure of reactions to noise. Dr Fields replied that he preferred the technique to that of using complaints. Several others expressed their opinions at this point. Dr Langdon asked what the complaint is worth? "Are we interested in complaints or annoyance?" he went on, adding that complaint activity is affected by social class, with higher social classes complaining more. Complaints are not solely a result of noise. Professor Rylander said the dose-response relationship is very weak if complaints are used as a measure of the response. He also suggested that a method for collecting data by means of activity disturbance should be developed. Mr Stanworth reported that British Rail was more likely to receive complaints about signals and suchlike than about the trains themselves. There are a variety of reactions to the railway he went on, and, although people do complain, it is not necessarily about the noise. To that, Dr Rathe added that people would be more likely to complain if they could see a chance to change the situation.
Mr Hemsworth then asked what the new English study will actually prove, to which Dr Fields answered that it will show the extent of annoyance at different noise levels and will give information which can be used as criteria.
Can we use the results for legislation, asked Mr Hemsworth. Dr Fields replied that the definition of "acceptable levels" such as would be used in legislation is a political decision which would be based both on the kind of dose-response relationship that is established by study and on the mixture of values and costs which would be considered by decision makers.
Dr Langdon wanted to know ifreports of activity disturbance are a more reliable measurement of reactions than respondents' reports of their annoyance. Dr Fields answered that in 363