Noise......

Dear All,
First of all thank you so much for your lots of inputs on privious thread Noise.....and with the referance previous thread on Noise I am raising a query that how you will defined that employee is having NIHL after audiometry because of age factor ( 50 yers or till 58 yers ) or his Occupation......? Is it there any test to find out the exact reson of NIHL.....?
waiting your feedbacks....
Regards,
SSB

Dear Mr. Munna Bhosale,
I have gone through this problem.
It is difficult to identify NIHL as natural hearing hearing loss also takes place because of aging of body.
In my previous assignment we had CNC machines which used to have a noise of @ 85dBA.
after 5 years at an average age of 35 years 5 out of 8 workmen have developed NIHL problem.
The only way is to have medical examination before the person joins the company and regular 6 monthly audiometry tests. Compare the results with previous tests and keep track of NIHL of all employees working in noisy area.
As soon as symptons are seen focus on Job rotation.
What CA we had taken in the previous assignment is " we have provided acoustic enclosure to the machines", isolating the operator from hazard.
We got very good results.
Thanks & Regards,
Sudhir

Dear SSB,
Check the OSHA 1910.95 App F may it will help you.
Safety and Health Topics | Occupational Noise Exposure - Standards
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Keep on touch.
Dear Sudhir,
Thanks for your participation.

Dear SSB
I had a discussion regarding this topic with one of the medical officer... He comment as follows:
"Audiometry is the best diagnostic method for identifying that the hearing loss is because of aging factor or due to NIHL... If the hearing loss is because of aging factor the audiometry report will shows that in almost all frequencies there will be a depth, means that person cannot hear proper in almost all the frequencies and in case of NIHL there will be a depth in high frequencies only...In addition to this we can judge whether the hearing loss is due to NIHL by cross checking the occupational history..."
Please let me know your comments...

Dear Sir
Thanks for your detailed write up on this topic...
Can you please let me know what is this CNC machine??? It's new to me...
I think, providing acoustic enclosures is very costly and not always practically possible... In what kind of industry did you succeed in implementing this?

Dear All
Got the following definition also regarding the topic from one of the book, may be useful:
Occupational deafness is a prescribed occupational disease which is described thus:
‘substantial sensorineural hearing loss amounting to at least 50 dB in each ear, being due in the case of at least one ear to occupational noise, and being the average of pure tone loss measured by audiometry over the 1, 2 and 3 KHz frequencies’.

Dear Sir,
Thanks for your reply,
I have disscussed with our ENT Dr. he told us the result cannot be a 100 % correct NIHL is due to Ageing factor or Occupational hearing loss but in maximum cases audiometry report shows deep frequencies as you said.
Regards,
SSB