Table 2.

Scheme of variables describing subjective responses to noise according to day/night period and noise sources

	Traffic only	Neighbourhood only	Traffic and neighbourhood	All sources
Day only	A t.	A n.	A (t. + n.)	A g.
Night only	SD t.	SD n.	SD (t. + n.)	SD g.
Day and night	(A + SD) t.	(A + SD) n.	(A + SD) (t. + n.)	(A + SD) g.

A t.=annoyance by traffic noise, A n.=annoyance by neighbourhood noise, A (t. + n.)=annoyance by traffic and neighbourhood noise, A g.=the general rate of noise annoyance, SD t.=sleep disturbance by traffic noise, SD n. =sleep disturbance by neighbourhood noise, SD (t. + n.)=sleep disturbance by traffic and neighbourhood noise, SD g.=the general rate of sleep disturbance by noise, (A + SD) t.=annoyance and sleep disturbance by traffic noise, (A + SD) n.= annoyance and sleep disturbance by neighbourhood noise, (A + SD) (t. + n.)=annoyance and sleep disturbance by traffic and neighbourhood noise, (A + SD) g.=the general rate of annoyance and sleep disturbance by noise.