Nocturnal road traffic noise LAeq(22h-08h) was measured inside
and outside the bedroom during seven consecutive nights using
Integrator Class 1 (inside) and Class 2 (outside) Sound Level Meter
(SLM) (Metravib). SLM Class 1 and 2 had a measurement range of
respectively 20–137 dB(A) and 30–137 dB(A).