ISO 2151 is this sound pressure level or sound power level?

[kiwitom235]

Question in the title...

I see values stated like this and dont know whether they mean sound power level or sound pressure level:

Noise level (ISO 2151): 66dB(A)

I would assume it is sound power level, but can someone confirm?

Tom

 

[IRstuff]

That should be described in the definition section:

https://www.iso.org/obp/ui/#iso:std:iso:2151:ed-2:v1:en

but db(A) usually refers to sound pressure level:

https://en.wikipedia.org/wiki/A-weighting

TTFN
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[Strong]

Read this:

https://www.iso.org/obp/ui/#iso:std:iso:2151:ed-2:v1:en

Walt

 

[chicopee]

66 db(A) is a sound level ( not sound pressure or sound power) which can be 1) can be calculated from the ratio of a sound pressure (units in micro pascal for example) measured with a sound pressure meter to some reference sound pressures (normally taken as 20 micro pascal for industrial noise),or 2) can also be calculated from the ratio sound power lever (units normally in watts) to some reference power level ( normally taken as 10^-12 watt). The (A) weighting factor suggest on the other hand that a sound level meter or analyzer that is set to a response sensitivity to the human ear was used to establish that 66 db(A). Also familiarize yourself with the "B" and "C" weighting scales. Fundamental of Industrial Hygiene by the National Safety Council is a good reference.

 

[jeyaselvan]

As per ISO 2151, it could either refer sound pressure or sound power. You have to get it clarified. If it is catalogue sepcification,it is often the sound pressure level. The manufacturers do not intend to publish higher numbers (sound power) in the catalogue.