Commentaries: Annex 6

(Art. 40 para. 1)

Exposure Limit Values for Industrial and Commercial Noise

1 Scope

¹The exposure limit values specified in Number 2 apply to noise: from industrial, commercial and agricultural installations; from goods handling in industrial, commercial and agricultural installations and at railway stations, aerodromes, etc.; from traffic within the perimeter of industrial and commercial installations and farmyards; from multi-storey car parks and from larger off-road car parks; from heating, ventilation and air-conditioning installations.

²Energy, waste processing and transport installations, aerial cableways and cable railways, ski lifts and racing tracks that are used regularly for sustained periods of time are considered equivalent to industrial and commercial installations.

2 Exposure Limit Values

Sensitivity level (Art. 43)	Planning value Lr in dB(A)		Impact threshold Lr in dB(A)		Alarm value Lr in dB(A)
	Day	Night	Day	Night	Day	Night
I	50	40	55	45	65	60
II	55	45	60	50	70	65
III	60	50	65	55	70	65
IV	65	55	70	60	75	70

3 Determination of the Rating Sound Level

31 Principles

¹The rating sound level Lr for industrial, commercial and similar types of noise is determined from the partial rating sound levels Lr,i for each noise phase as follows, whereby separate calculations are made for daytime (07 to 19 hours) and night-time (19 to 07 hours):

²The partial rating sound level Lr,i is determined for the average daily duration of the noise phase i as follows:

Lr,i = Leq,i + K1,i + K2,i + K3,i + 10 x log (ti/to)

where:

Leq,i is the equivalent continuous A-weighted sound level during the noise phase i;

K1,i is the level correction for the noise phase i;

K2,i is the level correction for the noise phase i;

K3,i is the level correction for the noise phase i;

ti is the average daily duration of the noise phase i in minutes;

to = 720 minutes.

³Noise phases are time periods in which the exposure point is subject to uniform noise with respect to sound level, frequency and pulse content.

32 Average Daily Duration of Noise Phases

¹The average daily duration (ti) of the noise phase i is calculated from its annual duration (Ti) and the annual number of working days (B) as follows:

ti = Ti/B

²For new or modified installations, the average daily duration of the noise phase i is determined from operational forecasts.

33 Level Corrections

¹Value of the level correction K1:

a. for noise according to Number 1 paragraph 1 letters a and b	5
b. for noise according to Number 1 paragraph 1 letter c	0
c. for noise according to with Number 1 paragraph 1 letter d	0 by day 5 at night
d. for noise according to Number 1 paragraph 1 letter e	5 by day 10 at night.

²The level correction K2 takes account of the audibility of the tonality content of the noise at the point of exposure and is equal to:

for non-audible tonality content 0
for weakly audible tonality content 2
for clearly audible tonality content 4
for strongly audible tonality content 6.

³The level correction K3 takes account of the audibility of the pulse content of the noise at the point of exposure and is equal to:

for non-audible pulse content 0
for weakly audible pulse content 2
for clearly audible pulse content 4
for strongly audible pulse content 6.

34 Air-to-Water Heat Pumps

¹In order to determine the rating sound level in the case of air-to-water heat pumps that are primarily used for space heating or for heating drinking water the sound power level at an outdoor temperature of 2°C is decisive.

²The FOEN shall recommend suitable measurement and calculation procedures for air-to-water heat pumps in accordance with the state of the art.

Annex 6