Müller BBM Group
Bavarian State Ministry
of the Interior

Almost 80 % of
all Germans
suffer due to
noise and

its consequences.

 

Federal Office of Statistics Wiesbaden

Interesting facts about noise

 

Noise protection walls can counter sound experienced as being annoying in two ways:

 

  • Sound dampening:
    The greater the mass that is subjected to a source of noise in closed form, the greater the effect. The insulation values of our system that is filled with soil total up to 67dB(A), depending on the product.

 

Changes to volume levels of just 1dB are perceptible to the human ear under certain conditions; a volume level adjustment of 10 dB corresponds with roughly the doubling and/or halving of volume that is experienced subjectively. The table lists volume levels and the corresponding noise sensitivity to some typical types of noise.

 

Noise level

Type of noise

Volume level

 Sensitivity to

 noise

 I

30 - 65 dB(A) psychological reaction

ticking of a quiet clock,

gentle rainfall, whispering
 30 dB(A)  very quiet
nearby whispering, quiet residential street  40 dB(A)  pretty quiet
Normal conversation  50 dB(A)  normal
Normal conversation at a distance of 1m, office noise  60 dB(A)  normal to loud

 II

65 - 90 dB(A)

Physiological reaction

loud conversation, shouting, car at a distance of 10m  70 dB(A)  loud to very loud
Road noise in the event of heavy traffic  80 dB(A)  very loud

 III

90 - 120 dB(A)

Damage to hearing,

Earache
loud factory hall  90 dB(A)  very loud
Car horn at a distance of 7m 100 dB(A)

 very loud to

 unbearable

Boiler maker 110 dB(A)

 very loud to

 unbearable

Aircraft engine 120 dB(A)

 unbearable

 to painful

  130 dB(A)

 Pain

 threshold

 

 

Doctors and acoustics researchers agree that raised levels of noise can damage your health. Anyone who is exposed to an average outdoor noise level during the daytime of over 65dB A, and of over 55db A during the night for long periods of time runs a high risk of developing high blood pressure and, as a consequence, a cardio-vascular disease. Hearing damage occurs after long term subjection to sound levels over and above 85dB A.

 

 


 

  • Sound absorption:
    This refers to how much sound is "swallowed" by the surface of the wall, rather than the noise that bounces off it.

 

With the naturawall system it is possible to achieve up to 16dB depending on the product.

 

 

Definition of sound absorption groups

Group Absorption DLa
A1 < 3 dB

not absorbent

A2 4 - 7 dB absorbent
A3 8 - 11 dB highly absorbent
A4 > 11 dB highly absorbent

 

 

 


 

 

RLS-90 concerning noise protection measures

 

  • Volume level reductions of up to 15dB(A) are possible
  • Shielding devices should be many times longer than the distance to the object requiring protection.
  • Shielding devices under 2m are not, generally, of any use
  • The visual link with the source of the noise must be interrupted
  • Shielding devices should be designed to be as unobtrusive as possible

 


 

Additional detailed information

 

on the subject of noise is available on the website of the Bavarian Ministry
of the Environment:

 

 

 

Easy. Fast. Quiet.