Maximum sound pressure level for motor

[JGOMEZL]

According API Standard 547, First Edition, Jan 2005, Art. 2.1.2: the A-weighted maximum sound level of the motor shall not exceed 85 dBA at any location at a reference distance of 3 ft (1 m) with motor operating at no load, full voltage, rated frequency and sinusoidal power.

We are purchasing a 2400 HP, 6.9 kV squirrel-cage induction motor from FENDER LOHER, Germany.

The results for the sound pressure level test were: 88 dBA, 3 dB in excess. The rest of tests were OK.

The question is: Are there an American Standard (Or another one) which establishes another criteria (logical criteria or common sense) in order to take adequate decision for approvement the motor of LOHER?

Juan Carlos Gomez - PDVSA - VENEZUELA

 

[plate]

The 85dB A weight sounds like the same standard for occupational exposure to noise for 8 hours. People exposed to 85dBA for 8 hours or more require hearing protection, as I seem to remember.

Perhaps you need to construct a noise barrier or enclosure or have employees where hearing protection. Take a look at the OSHA site. I am not sure how this relates to you country.

 

[muskiedog]

Equipment can be as load as it wants, but from a user stand point once you have identified that they are exposed to an excessive sound level will then require audiometric testing of the employees intially and then annually there after. This would only be for employees exposed to the excessive levels. I believe OSHA has a threshold level of 90 dBs and once a hearing loss is recorded you then are require to use the 85 dBs level.

It will also require training employees on hearing protection, proper fitting, and how and when to use it.

I would build a barrier around the equipment to reduce the expose levels.

You need to do the testing at the operators location not at the equipment or employees who are working in the vacinity of the equipment.

Engineer it out. Provide a barrier against. Last provided PPE if the others do not work.

Hope this helps

 

[RayS]

For an acceptance test, I'd want to know what the spec was for the environment, IEutdoor/anechoic condition or some specified indoor condition

...Engineer it out. Provide a barrier against. Last provided PPE if the others do not work...

Yep. Only thing I would add is that the surrounding area has a big influence on the SPL's. Maybe add some absorbtion.