noise prevention in factories-approved

Noise Prevention in Factories 1

Noise Prevention in Factories

Ir. Gan Chun Chet

Aug 2009


Introduction On Noise

• Prevention Of Noise Problem In Factories• Reference Material :

Factory And Machinery Act 1967, Noise Regulation 1989

• Other Supporting Data :- Research Results From A Foreign Company- Noise Study In A Factory, With Data Based On Audiometric Test Results


Introduction On Noise

• Severity Of The Problem- Damage To Hearing Ability, Causing Hearing Impairment On The Ear

• Cause Of Problem- Noise

• Remedy- Noise Prevention


Types of Noise

• Noise Travel Into Our Ear- Propagation Of Sound Wave To The Ear Can Damage Our Ear- Long Exposure To Noise At Noisy Areas Effect Us


Types of Noise

• Type Of Noise Source (Point, Line, etc.)

• Types Of Noise- Very Strong Pressure Fluctuation- Repetitive Or Cyclical Noise- Pulsation Noise


Noise Measurement

• Noise Unit Of Measurement Is In Decibel (dB)

• The Weighted Sound Level Unit Is dB(A)• Sound Level Is The Noise Level• Noise Is Unwanted Sound• Equipment To Measure Noise Inside Plant

– Noise Dosimeter• Audiometric Test (Using Tone) To Find

Out A Person Hearing Level


Research Findings (by a Foreign Company)

• Following Are Some Research Finding From A Foreign Company

• Normal Hearing Level With Age

• Hearing Loss Due To Exposure With Age

• Hearing Ability Of Maintenance Personnel


A Real Case – A Factory in Malaysia

• The Following Is A Real Case Of Workers Hearing Ability With Age

• Different Graphs Plotted With Years Of Employment And Age


Real Case (Main Data)



• Cluster Of Dense Population Observed On Sample Group

• Subject Age GroupDensely Populated Area 36 To 50Second Dense Area 16 To 30

• Audiogram Distribution Found That Most Of The Sample Workers Noise Receptivity Level Are The Region Of 5 To 34 dB


Real Case (Less than 10 years service)

• Sample Of Workers With Service Employment 10 Years Or Less Were Separated From The Main Sample Group.

• Hearing Receptivity Was Plotted Against Age Of Sample Workers. Similar Pattern Corresponded To Main Sampling Group Was Observed(Sampled Of Production Workers At Floor Level)



• Two Cluster Group Were Observed On The Chart. However, The Size Of The Cluster Group Is As Follow.

• Subject Age GroupCluster 1 16 To 30Cluster 2 36 To 50

• Results - Below 20 dB (Cluster 1)- Below 30 dB (Cluster 2)


Real Case (More than 10 years service)

• Analyzing Chart For Employment With Greater Than 10 Years, It Was Found One Cluster.

• These Spread Over Between Age Group Of 36 To 55 Years Old.

• The Receptivity Level Of The Cluster Is Higher When Compare To Age Group Between 16 To 30 Years Of Age.



• One GroupSubject Age GroupCluster 1 35 To 55

• Results - Below 30 Db

• Cases Of Individual Hearing Receptivity Leaving The Cluster Group Is Also Noticed Shown In Line “A”


Real Case – Statistics(Summary of Finding)

• Employment Less Than 10 Years• (16 – 35 Years Old)

60 – 100 dB 3 Person40 – 60 dB 4 Person30 – 40 dB 11 PersonTotal = 18 Person

• (36 – 60 Years Old)60 – 100 dB 4 Person40 – 60 dB 5 Person30 – 40 dB 12 PersonTotal = 21 Person


Real Case – Statistics (Summary of Finding)

• Employment More Than Or Equal To 10 Years

• (30 – 55 Years Old)60 – 100 Db 4 Person40 – 60 Db 13 Person30 – 40 Db 18 PersonTotal = 35 Person


Factories and Machinery Act 1967 (FMA)

• A Standard Threshold Shift – Average Shift Of 10 dB At Frequencies 2000 Hz, 3000hz And 4000 Hz Relative To The Baseline Audiogram

• A Hearing Impairment – An Impair In The Ability In Hearing (Ask An Ear Specialist)

• Permanent Disability – Permanent Damage (Very Serious!)

• (Consult Doctors Or Specialist! Hearing Problem Must Not Be Taken Lightly)

• Also Refer To FMA Available In Bookstores


Factories and Machinery Act 1967 (FMA)

• Factories And Machinery, Noise Exposure Regulations, 1989

• Employees Need To Check For A Baseline Reading (Required By Law)

• Noise Level Collected And Recorded At 500, 1000, 2000, 3000 & 4000Hz

• Required By Law Of Malaysia That The Permissible Exposure Limit Is (Refer To Schedule)- 85 dB(A) For 16 Hours Duration Per Day,- 90 dB(A) For 8 Hours Duration Per Day, etc. Per Schedule- Nobody Shall Be Exposed To Noise Level Exceeding 115 dB(A) At Any Time


Factories and Machinery Act 1967 (Noise Regulation)

• Some Examplese.g. The Sum Of Hearing Threshold Levels Shows An Increase Of 30 dB Compared To Preceding Level. Very Serious Shift!

• Case : Less Than 10 Yrs Employment, 1st Cluster 20 dB And Below. 2nd Cluster 30 dB And Below

: More Than 10yrs Employment, Cluster 30 dB and Below

: Some Able To Hear Only At 90 dB! Damaged

• Less Than 85 dB(A) Exposure Limit A Day


Factories and Machinery Act 1967

• Take Note Of Threshold Shift! DO NOT Play With This!

• Reduce Noise Level (Engineering Measures)

• Avoid Noisy Area (Admistrative Control)

• Consult Noise Consultant Or Ear Specialist!


Noise Consultant and Audiometric Test

• Noise Consultant Report On Condition Of The Plant

• Report Will Identify Noisy Areas

• Recommends Remedies


Noise Consultant and Audiometric Test

• Test To Find Out The Hearing Ability Of A Person

• Audiometric Test Result Indicates Noise Receptivity Of A Person

• Low Frequencies Or High Frequencies Noise That A Person’s Is Able To Hear Are Tested


Noise Mapping

• Noise Mapping By Noise Consultant

• Look At Noisy Places And Plot Real Noise Level At Floor Level.

• Noise Exposure Measurement To Find Out The Daily Exposure Limit Of A Worker

Above 90 dB(A)

85- 90 dB(A)

Below 85 dB(A)


Hearing Conservation Program

• Hearing Conservation Program- Engineering Control(To Install Enclosure At Rotating Equipment, To Reduce Device Noise e.g. Control Valve & Relief Valve, To Prevent Noise From Traveling Into The Control Room)

Enclosure

Machine

Limit noise out of the enclosure

Control Room

Limit noise to the control room


Adminstration

• - Administrative Control(To Move Workers In And Out Of Noisy Area (Take Note Of Threshold Shift, Very Dangerous

• So FMA Mentioned To Limit Daily Exposure To Noise By Control Of Work Schedule, Very Difficult To Practice), Constant Monitoring, Do Not Allow People To Enter Noisy Areas, Sign Board Of High Noise Areas, etc.)

HIGH NOISE AREA

- WEAR EAR MUFFLE


Cases of Over Exposure

• Limits of Audibility

• Also consult a ear specialist


Cases of Over Exposure


Noise Prevention

• Prevent Exposure to Unwanted Noise- Avoid Going Into Noisy Area- Do Not Allow Unwanted Noise To Enter The Ear- Reduce Noise Source To The Acceptable Level

- Do a noise mapping to understand the areas of noise source and the allowable area of work- Check you ear condition by audiometric test


Remedy

• Remedy- Limit the noise source- Enclosure the noisy source- Wear Protective Ear Plugs or Muffles- Prevent workers from going into noisy area- Sign boards to inform workers of noisy area


Conclusion

• FMA 1967 – Get it from bookstore (MPH, Popular, etc.)

• Slides, Noise Chart and Excel File, if required – Get it from Zul.


Noise Chart

• Chart

• Identify a factory worker’s hearing ability whether it is healthy (within the limit)

• Please also refer to test result report from a qualify doctor


20 dB

30 dB

20 60

10 dB

30

Worker’s Age (Year)

40 50

Normal Hearing Ability

Category 3

Category 2

Category 1

Category 1 : Very GoodCategory 2 : GoodCategory 3 : Caution

Noise Chart


Noise Records - Excel File

• Excel File

• Measure the audiometric test result and record.

• Warning Limit (Standard Threshold Shift)


Noise Prevention(Own Notes)

• Introduction On Noise• Type of Noise• Types of Noise Measurement

• Research Findings From a Foreign Company• A Real Case on Audiometric Test Result on Factory Workers

• The Law of Malaysia, FMA 1967 (Noise Regulation 1989)

• Noise Consultants and Audiometric Test• Noise Mapping

• Engineering and Administration Control• Cases of Over Exposure – See a Ear Specialist

• Noise Prevention• Remedy

• Conclusion

• Noise Chart• A Excel File

• An Article on A Real Case

noise prevention in factories-approved

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