Dear Munna,
I appreciate your attempt in producing the PPT!
However, if for once you sit back and ask the following types of questions, you will realize that something is missing from your presentation. When we create a safety/health presentation, the individual who reviews it should not be left with unanswered related issues. If you are in the profession, kindly take this in good spirit; incorporate the answers to the questions below and more if you have them, which will enhance your professional presentation.
- What is sound if noise is unwanted sound?
- What are the characteristics of noise?
- How do people differentiate between sound and noise?
- What is the anatomy of the ear?
- How do we hear, or what is the hearing mechanism?
- How does noise-induced hearing loss occur?
- What is dB?
- Is noise level measured only in dBA or up to dBZ?
- What instrument is used for measuring noise?
- Are there multiple types of measurement for noise?
- What is audiometry?
- How do you select ear protection?
- What are the differences between earplugs, canal caps, and muff-type ear defenders?
- Is a fit test necessary for ear defenders?
- How do you maintain the ear defenders?
Regards,
Kesava Pillai
From India, Kollam
I appreciate your attempt in producing the PPT!
However, if for once you sit back and ask the following types of questions, you will realize that something is missing from your presentation. When we create a safety/health presentation, the individual who reviews it should not be left with unanswered related issues. If you are in the profession, kindly take this in good spirit; incorporate the answers to the questions below and more if you have them, which will enhance your professional presentation.
- What is sound if noise is unwanted sound?
- What are the characteristics of noise?
- How do people differentiate between sound and noise?
- What is the anatomy of the ear?
- How do we hear, or what is the hearing mechanism?
- How does noise-induced hearing loss occur?
- What is dB?
- Is noise level measured only in dBA or up to dBZ?
- What instrument is used for measuring noise?
- Are there multiple types of measurement for noise?
- What is audiometry?
- How do you select ear protection?
- What are the differences between earplugs, canal caps, and muff-type ear defenders?
- Is a fit test necessary for ear defenders?
- How do you maintain the ear defenders?
Regards,
Kesava Pillai
From India, Kollam
@Mr. Munna,
Nice ppt. Thanks. Please go through the questions asked by Kesava sir and try to revert back with adequate answers. He gave us this opportunity to become perfect in this hazard type, and I hope he will guide us in all such areas one by one.
Regards,
Abhay
From India, Mumbai
Nice ppt. Thanks. Please go through the questions asked by Kesava sir and try to revert back with adequate answers. He gave us this opportunity to become perfect in this hazard type, and I hope he will guide us in all such areas one by one.
Regards,
Abhay
From India, Mumbai
Dear Kesav Sir,
I have added my inputs on this thread. Please review and advise me.
Noise is unwanted sound, then what is sound?
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas. It is composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.
What are the characteristics of noise?
There are two important characteristics of sound or noise - frequency and loudness.
How do people differentiate between sound and noise?
Sound is a kind of vibration that travels through air, water, and is sensed by the ear. It is a thing that can be heard, such as music, speech, and other sounds like film dialogues. We can adjust the volume of sound as per our preference, but noise is a combination of sounds that cannot be clearly heard or individually adjusted. For example, in a meeting, multiple people talking can create noise. In a market, the various sounds of buying and selling merge into noise. A clear sound can be heard distinctly from a particular source, while noise is a mixture of indistinct sounds from various directions.
How do we hear, and what is the hearing mechanism?
Sound waves hit the eardrum (tympanic membrane), which transmits the impulse through the three bones of the middle ear to the inner ear. The inner ear transduces the signal into an electrical signal that the brain can interpret.
What is dB?
The decibel (dB) is used to measure sound levels and is also widely used in electronics, signals, and communication. It is a logarithmic unit that describes a ratio, which may involve power, sound pressure, voltage, intensity, or other factors.
What instrument is used for measuring noise?
A decibel meter.
What is audiometry?
Audiometry is the testing of a person's ability to hear various sound frequencies using electronic equipment called an audiometer.
How to select ear protection?
Please see the attached...
Dear Munna,
Thank you for your noise/sound-related PPT.
Thanks & Besafe,
Raghu
Please review this. Thanks in advance.
From United States, Fpo
I have added my inputs on this thread. Please review and advise me.
Noise is unwanted sound, then what is sound?
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas. It is composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.
What are the characteristics of noise?
There are two important characteristics of sound or noise - frequency and loudness.
How do people differentiate between sound and noise?
Sound is a kind of vibration that travels through air, water, and is sensed by the ear. It is a thing that can be heard, such as music, speech, and other sounds like film dialogues. We can adjust the volume of sound as per our preference, but noise is a combination of sounds that cannot be clearly heard or individually adjusted. For example, in a meeting, multiple people talking can create noise. In a market, the various sounds of buying and selling merge into noise. A clear sound can be heard distinctly from a particular source, while noise is a mixture of indistinct sounds from various directions.
How do we hear, and what is the hearing mechanism?
Sound waves hit the eardrum (tympanic membrane), which transmits the impulse through the three bones of the middle ear to the inner ear. The inner ear transduces the signal into an electrical signal that the brain can interpret.
What is dB?
The decibel (dB) is used to measure sound levels and is also widely used in electronics, signals, and communication. It is a logarithmic unit that describes a ratio, which may involve power, sound pressure, voltage, intensity, or other factors.
What instrument is used for measuring noise?
A decibel meter.
What is audiometry?
Audiometry is the testing of a person's ability to hear various sound frequencies using electronic equipment called an audiometer.
How to select ear protection?
Please see the attached...
Dear Munna,
Thank you for your noise/sound-related PPT.
Thanks & Besafe,
Raghu
Please review this. Thanks in advance.
From United States, Fpo
Additional Inputs ( In Blue Colour) From My side after discussing with my S.O.:
I was add my inputs on this thread please review and advice me. . .
Noise is unwanted sound then what is sound?
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.
What are the characteristics of noise?
There are two important characteristics of sound or noise - frequency and loudness.
FREQUENCY- perceived as pitch , INTENSITY- perceived as loudness , NATURE- steady-state vs. impulse/impact ,DURATION- length of time exposed
How people differentiate between sound and noise?
sound is a kind of vibration which travel through air, water, and are sensed by the ear. a thing that can be heard. This is from music, speech, and others like films dialogs etc., one thing in this matter is that we can increase the volume of sound or decrease as per our taste if it is from radio, television, computers and man operative machines.whereas,a noise is a sound from one and more at a time which can not be heard clearly and only mixed sounds will be heard. you can not increase or decrease the noise. If a meeting, there will be noise among the people talking each other besides the speaker going on talking. in a shandy, there we can hear the noise since several persons are on buying and selling. in an office one is talking on mobile, phone ringing another side, ring tones in some person's hands, loud conversations with one and another etc., this is called noise. Even, a music in public place with loud voice will also be a noise in general, a sound is a vibration from a particular machine, place or material which can be heard clearly whereas a noise a mixed vibrations that will come to us from all directions. A sound can be clear and can be able to hear, whereas a noise will not be clear and can not be heard.
If you have to raise your voice to be heard by someone standing within 3 foot (arm's length) then the level is most likely above the hazardous noise level
How we hear or what is the hearing mechanism?
Sound waves hit the ear drum ("tympanic membrane"), which transmits the impulse through the three bones of the middle ear, which transmit the sound wave impulses to the inner ear, which "transduces" the signal into a sort of electrical signal the brain can interpret.
The decibel ( dB) is used to measure sound level, but it is also widely used in electronics, signals and communication. The dB is a logarithmic unit used to describe a ratio. The ratio may be power, sound pressure, voltage or intensity or several other things.
What is the instrument used for measuring noise ?
decibel meter
What is audiometry ?
Audiometry is the testing of a person's ability to hear various sound frequencies. The test is performed with the use of electronic equipment called an audiometer.
How to maintain the ear defenders?
Keep clean with mild soap and water and dry before using
Replace when material hardens/cracks or does not clean
Check for cracks on earphone seals, headband tension and replace as needed
How to select ear protection ?
Please see the attached . . .
Please review this thanks in advance. . .
Raghuji!!!!
Thanks for your inputs
Regards,
Abhay
From India, Mumbai
I was add my inputs on this thread please review and advice me. . .
Noise is unwanted sound then what is sound?
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.
What are the characteristics of noise?
There are two important characteristics of sound or noise - frequency and loudness.
FREQUENCY- perceived as pitch , INTENSITY- perceived as loudness , NATURE- steady-state vs. impulse/impact ,DURATION- length of time exposed
How people differentiate between sound and noise?
sound is a kind of vibration which travel through air, water, and are sensed by the ear. a thing that can be heard. This is from music, speech, and others like films dialogs etc., one thing in this matter is that we can increase the volume of sound or decrease as per our taste if it is from radio, television, computers and man operative machines.whereas,a noise is a sound from one and more at a time which can not be heard clearly and only mixed sounds will be heard. you can not increase or decrease the noise. If a meeting, there will be noise among the people talking each other besides the speaker going on talking. in a shandy, there we can hear the noise since several persons are on buying and selling. in an office one is talking on mobile, phone ringing another side, ring tones in some person's hands, loud conversations with one and another etc., this is called noise. Even, a music in public place with loud voice will also be a noise in general, a sound is a vibration from a particular machine, place or material which can be heard clearly whereas a noise a mixed vibrations that will come to us from all directions. A sound can be clear and can be able to hear, whereas a noise will not be clear and can not be heard.
If you have to raise your voice to be heard by someone standing within 3 foot (arm's length) then the level is most likely above the hazardous noise level
How we hear or what is the hearing mechanism?
Sound waves hit the ear drum ("tympanic membrane"), which transmits the impulse through the three bones of the middle ear, which transmit the sound wave impulses to the inner ear, which "transduces" the signal into a sort of electrical signal the brain can interpret.
How noise induced hearing loss takes place ?
NIHL : Initially, exposure to noise causes a loss of sensitivity to high frequency (high pitch) sound. Continued exposure results in damage to mid frequency region as well. One can experience progressive high frequency hearing loss and not be aware of it until it becomes severe .and how it happens :
ACOUSTIC TRAUMA – ONE TIME EXPOSURE TO LOUD SOUND
OR DAILY EXPOSURES TO MODERATELY LOUD SOUNDS
NIHL : Initially, exposure to noise causes a loss of sensitivity to high frequency (high pitch) sound. Continued exposure results in damage to mid frequency region as well. One can experience progressive high frequency hearing loss and not be aware of it until it becomes severe .and how it happens :
ACOUSTIC TRAUMA – ONE TIME EXPOSURE TO LOUD SOUND
OR DAILY EXPOSURES TO MODERATELY LOUD SOUNDS
Noise level is taken only in dBA or more up to dBZ ?
About dBZ - ??????
for impulse/impact noise sources - heard about dBP
What is dB ?About dBZ - ??????
for impulse/impact noise sources - heard about dBP
The decibel ( dB) is used to measure sound level, but it is also widely used in electronics, signals and communication. The dB is a logarithmic unit used to describe a ratio. The ratio may be power, sound pressure, voltage or intensity or several other things.
What is the instrument used for measuring noise ?
decibel meter
What is audiometry ?
Audiometry is the testing of a person's ability to hear various sound frequencies. The test is performed with the use of electronic equipment called an audiometer.
How to maintain the ear defenders?
Keep clean with mild soap and water and dry before using
Replace when material hardens/cracks or does not clean
Check for cracks on earphone seals, headband tension and replace as needed
How to select ear protection ?
Please see the attached . . .
Please review this thanks in advance. . .
Raghuji!!!!
Thanks for your inputs
Regards,
Abhay
From India, Mumbai
Dear abhay, Good work. . .Thanks for your input on this matter.Seniors Please come forward put on your inputs and advice us. . . Thanks in advance. . . Thanks & Besafe Raghu
From United States, Fpo
From United States, Fpo
Dear friends,
Reghu and Abhay, both your attempts are very well appreciated. Almost all the answers are reasonably good.
I am posting the answers but partly. In subsequent weeks, I will post the remaining also.
1. A vibrating body pushes on molecules, creating a series of pressure waves that radiate out from the source of the vibration, and we call it sound. Sound can be wanted or unwanted at times. Physically, sound and noise are the same. It depends on the receiver's mood. However, in terms of occupational health, noise can be defined as any sound that is intense enough to damage hearing.
Thus, a sound wave is a series of these compressions and rarefactions traveling through a substance. The individual molecules do not travel; rather, they vibrate rhythmically back and forth. Sound, in non-technical terms, is variation in air pressures, above and below atmospheric.
2. Intensity or loudness and frequency or pitch.
3. With one's changing mood, the same sweet sound of music can be noise at a different occasion.
4. Outer ear, eardrum, the three smallest bones in the body called anvil, hammer, and stirrup, and the cochlea, a tubular section containing hair cells. Photographs and pictures are available in plenty.
5. Your outer ear collects sound waves and channels them down the ear canal to a thin, tight piece of skin called the Tympanic membrane (eardrum). The eardrum vibrates in response to these pressure waves and pushes on the small bones of your middle ear. These bones act like a set of levers, transferring their mechanical motion to a fluid-filled structure in the inner ear, called the cochlea. In the cochlea, cells with tiny sensing hairs transform the fluid movement into electrical signals. These signals travel along the auditory nerve to your brain. Once in the brain, the nerve signals are decoded and processed into what we recognize as sound.
6. Due to excessive noise, the hair cells get destroyed, and that particular frequency sound connected with the destroyed hair cells will not be received anymore.
7. The unit of sound measurement is the "decibel" (abbreviated dB), which is 1/10 of a bel, named in honor of Alexander Graham Bell. The higher the number of decibels, the louder the sound. One decibel represents the weakest sound audible. A whisper would read about 10 decibels on the sound level meter.
8. Measurements are in dBA, dBB, or dBC. However, for noise conservation, we are quite particular about the speech range of frequencies. dBA is connected with this filtering out other frequencies. Thus, we prefer dBA for measurement in connection with noise conservation.
9. Noise is measured using a sound level meter.
10. We require a frequency analyzer too. Intensity alone is not sufficient. Intensity should be checked along with an octave band analyzer (frequency).
Regards,
Kesava Pillai
From India, Kollam
Reghu and Abhay, both your attempts are very well appreciated. Almost all the answers are reasonably good.
I am posting the answers but partly. In subsequent weeks, I will post the remaining also.
1. A vibrating body pushes on molecules, creating a series of pressure waves that radiate out from the source of the vibration, and we call it sound. Sound can be wanted or unwanted at times. Physically, sound and noise are the same. It depends on the receiver's mood. However, in terms of occupational health, noise can be defined as any sound that is intense enough to damage hearing.
Thus, a sound wave is a series of these compressions and rarefactions traveling through a substance. The individual molecules do not travel; rather, they vibrate rhythmically back and forth. Sound, in non-technical terms, is variation in air pressures, above and below atmospheric.
2. Intensity or loudness and frequency or pitch.
3. With one's changing mood, the same sweet sound of music can be noise at a different occasion.
4. Outer ear, eardrum, the three smallest bones in the body called anvil, hammer, and stirrup, and the cochlea, a tubular section containing hair cells. Photographs and pictures are available in plenty.
5. Your outer ear collects sound waves and channels them down the ear canal to a thin, tight piece of skin called the Tympanic membrane (eardrum). The eardrum vibrates in response to these pressure waves and pushes on the small bones of your middle ear. These bones act like a set of levers, transferring their mechanical motion to a fluid-filled structure in the inner ear, called the cochlea. In the cochlea, cells with tiny sensing hairs transform the fluid movement into electrical signals. These signals travel along the auditory nerve to your brain. Once in the brain, the nerve signals are decoded and processed into what we recognize as sound.
6. Due to excessive noise, the hair cells get destroyed, and that particular frequency sound connected with the destroyed hair cells will not be received anymore.
7. The unit of sound measurement is the "decibel" (abbreviated dB), which is 1/10 of a bel, named in honor of Alexander Graham Bell. The higher the number of decibels, the louder the sound. One decibel represents the weakest sound audible. A whisper would read about 10 decibels on the sound level meter.
8. Measurements are in dBA, dBB, or dBC. However, for noise conservation, we are quite particular about the speech range of frequencies. dBA is connected with this filtering out other frequencies. Thus, we prefer dBA for measurement in connection with noise conservation.
9. Noise is measured using a sound level meter.
10. We require a frequency analyzer too. Intensity alone is not sufficient. Intensity should be checked along with an octave band analyzer (frequency).
Regards,
Kesava Pillai
From India, Kollam
Dear Friends,
Here are the remaining points:
11. An audiometric examination tests hearing acuity. The audiometric testing procedure tests one's hearing threshold at a range of different frequencies. The hearing threshold is the lowest level at which one is able to detect the test tone at each frequency and is determined by his response. Tests are performed in both ears.
12. Apart from all other general considerations for selecting any PPE, the manufacturer has to give the NRR (noise reduction ratio) of the ear defender. NRR will never be correct because of leaks in the seal, vibration, and improper insertion. NRR application is as noted below:
a. Earmuffs - Subtract 25% from the manufacturer's labeled NRR.
b. Formable earplugs - Subtract 50% from the manufacturer's labeled NRR.
c. All other earplugs - Subtract 70% from the manufacturer's labeled NRR.
I am sure that most safety officers may not have even heard about this. However, it is a very serious point to be strictly followed.
13. Earplugs and canal caps are inserted into the ear. Earplugs are squeezed into the ear canal and expand to seal. Canal caps are rigid and pushed in seal and will not reshape inside and hence not much preferred. Ear Muffs are to seal at the periphery of the ear in total which will give a better seal if selected properly.
14. Ear defenders require a fit test without which noise reduction as necessary cannot be assured.
15. Disposable type – throw them off after day's use. Others clean and disinfect to store in hygienic condition. Replace defective ones. Check every time before using. Never use ear defenders used by others.
Regards,
Kesava Pillai.
From India, Kollam
Here are the remaining points:
11. An audiometric examination tests hearing acuity. The audiometric testing procedure tests one's hearing threshold at a range of different frequencies. The hearing threshold is the lowest level at which one is able to detect the test tone at each frequency and is determined by his response. Tests are performed in both ears.
12. Apart from all other general considerations for selecting any PPE, the manufacturer has to give the NRR (noise reduction ratio) of the ear defender. NRR will never be correct because of leaks in the seal, vibration, and improper insertion. NRR application is as noted below:
a. Earmuffs - Subtract 25% from the manufacturer's labeled NRR.
b. Formable earplugs - Subtract 50% from the manufacturer's labeled NRR.
c. All other earplugs - Subtract 70% from the manufacturer's labeled NRR.
I am sure that most safety officers may not have even heard about this. However, it is a very serious point to be strictly followed.
13. Earplugs and canal caps are inserted into the ear. Earplugs are squeezed into the ear canal and expand to seal. Canal caps are rigid and pushed in seal and will not reshape inside and hence not much preferred. Ear Muffs are to seal at the periphery of the ear in total which will give a better seal if selected properly.
14. Ear defenders require a fit test without which noise reduction as necessary cannot be assured.
15. Disposable type – throw them off after day's use. Others clean and disinfect to store in hygienic condition. Replace defective ones. Check every time before using. Never use ear defenders used by others.
Regards,
Kesava Pillai.
From India, Kollam
Dear all,
Thank you for the great discussion, but I apologize for being late.
I would also like to add something:
- Sound has both frequency and intensity.
- Frequency or pitch is the number of sound vibrations per second.
- The higher the frequency, the higher the pitch.
- Intensity refers to the degree of strength or energy.
- Noise-Induced Hearing Loss: i) Frequency, ii) Intensity.
- Intensity over 130 dB is painful and can damage hearing.
- Critical level: 85-120 dB is not painful but can damage ears.
Consequences:
1. Difficulty in hearing background noise.
2. Specific hearing limitations; loss occurs in high frequencies.
OHSAS requirements for training program:
1. Employee Training: i) Effects of noise, ii) Hearing protection, iii) Audiometric test, iv) Measuring noise.
2. Exposure monitoring.
3. Audiometric test.
4. Employee follow-up.
5. Record keeping.
6. Noise control.
7. Hearing Protection Devices.
To measure noise:
- Dosimeter: Body-worn instrument that measures and stores sound over time and can be read later.
- Engineering Surveys: Require sophisticated acoustical equipment that registers dB level, frequency, and intensity of noise from machinery.
- Audiometric Test: Within 6 months of first exposure to critical level. It measures the softest sound you can hear at each test frequency.
Standard Threshold Shift: Significant but decreases in the ability to hear at frequencies first affected by noise exposure. Notify within 21 days.
Some more information will be added soon... Lights are gone and I need to log out.
From India, Udaipur
Thank you for the great discussion, but I apologize for being late.
I would also like to add something:
- Sound has both frequency and intensity.
- Frequency or pitch is the number of sound vibrations per second.
- The higher the frequency, the higher the pitch.
- Intensity refers to the degree of strength or energy.
- Noise-Induced Hearing Loss: i) Frequency, ii) Intensity.
- Intensity over 130 dB is painful and can damage hearing.
- Critical level: 85-120 dB is not painful but can damage ears.
Consequences:
1. Difficulty in hearing background noise.
2. Specific hearing limitations; loss occurs in high frequencies.
OHSAS requirements for training program:
1. Employee Training: i) Effects of noise, ii) Hearing protection, iii) Audiometric test, iv) Measuring noise.
2. Exposure monitoring.
3. Audiometric test.
4. Employee follow-up.
5. Record keeping.
6. Noise control.
7. Hearing Protection Devices.
To measure noise:
- Dosimeter: Body-worn instrument that measures and stores sound over time and can be read later.
- Engineering Surveys: Require sophisticated acoustical equipment that registers dB level, frequency, and intensity of noise from machinery.
- Audiometric Test: Within 6 months of first exposure to critical level. It measures the softest sound you can hear at each test frequency.
Standard Threshold Shift: Significant but decreases in the ability to hear at frequencies first affected by noise exposure. Notify within 21 days.
Some more information will be added soon... Lights are gone and I need to log out.
From India, Udaipur
Dear all,
Here is some more information that was left out in the above post.
*Point of control of Noise:
i) At the source - lubricating moving/rotating parts, tightening vibrating surfaces, replacing old parts
ii) By routes traveled - by using sound-absorbing materials such as cushioning, padding using rubber parts
iii) Individual exposure - cover metal walls with insulation, make sound barriers.
*Hearing Protection:
i) Ear plug
ii) Ear muff
iii) Banded Protection - Inserted in the ear canal to block noise.
*Noise Reduction Rating (NRR): Hearing protection devices are rated for their effectiveness in decreasing noise. This is called NRR.
NRR is compared to the work environment's monitored noise level.
To calculate adequate protection: Divide NRR in half.
*EAR PLUG: (Reducing rating from 21-33 dB)
i) Formable - fine glass fiber, wax-filled cotton, expandable plastic, or foam.
One-time use, decrease sound by expanding to seal the ear canal opening.
ii) Customer molded - Designed for individuals, silicone, rubber, plastic molding
iii) Pre-molded - Silicone, rubber, plastic; Vary in size, shape, fits to seal the ear.
ADVANTAGES of Earplug:
Inexpensive, portable, comfortable, do not interfere with headgear, Do not restrict head movements.
Disadvantages:
Difficult to fit,
Dirt into the ear, lost, fall out, protection level varies.
*BANDED PLUGS: Soft form, rubber, soft plastic, Plastic cover sponge,
Lowest NRR - 17 to 25 dB reduction may be appropriate as low as 90 dB, not always versatile with headgear.
*FORM EARPLUGS: Highest NRR
Protection depends on how well it fits in the ear.
Regards,
Hansa
From India, Udaipur
Here is some more information that was left out in the above post.
*Point of control of Noise:
i) At the source - lubricating moving/rotating parts, tightening vibrating surfaces, replacing old parts
ii) By routes traveled - by using sound-absorbing materials such as cushioning, padding using rubber parts
iii) Individual exposure - cover metal walls with insulation, make sound barriers.
*Hearing Protection:
i) Ear plug
ii) Ear muff
iii) Banded Protection - Inserted in the ear canal to block noise.
*Noise Reduction Rating (NRR): Hearing protection devices are rated for their effectiveness in decreasing noise. This is called NRR.
NRR is compared to the work environment's monitored noise level.
To calculate adequate protection: Divide NRR in half.
*EAR PLUG: (Reducing rating from 21-33 dB)
i) Formable - fine glass fiber, wax-filled cotton, expandable plastic, or foam.
One-time use, decrease sound by expanding to seal the ear canal opening.
ii) Customer molded - Designed for individuals, silicone, rubber, plastic molding
iii) Pre-molded - Silicone, rubber, plastic; Vary in size, shape, fits to seal the ear.
ADVANTAGES of Earplug:
Inexpensive, portable, comfortable, do not interfere with headgear, Do not restrict head movements.
Disadvantages:
Difficult to fit,
Dirt into the ear, lost, fall out, protection level varies.
*BANDED PLUGS: Soft form, rubber, soft plastic, Plastic cover sponge,
Lowest NRR - 17 to 25 dB reduction may be appropriate as low as 90 dB, not always versatile with headgear.
*FORM EARPLUGS: Highest NRR
Protection depends on how well it fits in the ear.
Regards,
Hansa
From India, Udaipur
Dear Hansa,
Thanks for all your inputs, especially on this Noise/Sound thread.
Dear Kesav, Hansa, Abhay,
Thanks a lot for sharing valuable information regarding noise/sound. This thread has been particularly helpful in expanding my knowledge about noise/sound.
Dear Members,
If anybody has questions, please come forward; otherwise, we will close this thread.
From United States, Fpo
Thanks for all your inputs, especially on this Noise/Sound thread.
Dear Kesav, Hansa, Abhay,
Thanks a lot for sharing valuable information regarding noise/sound. This thread has been particularly helpful in expanding my knowledge about noise/sound.
Dear Members,
If anybody has questions, please come forward; otherwise, we will close this thread.
From United States, Fpo
Dear Seniors,
I am new to this site, and it is a really great platform for learning for fresh candidates.
1) Is any special training required for noise monitoring?
2) Who is the responsible person for monitoring noise (Safety Officer or Environmental Personnel)?
It was a really great discussion on noise, and I would like to know the answers to these queries.
Thanks in advance for your inputs.
Regards,
Ramchandra
From India, Kolhapur
I am new to this site, and it is a really great platform for learning for fresh candidates.
1) Is any special training required for noise monitoring?
2) Who is the responsible person for monitoring noise (Safety Officer or Environmental Personnel)?
It was a really great discussion on noise, and I would like to know the answers to these queries.
Thanks in advance for your inputs.
Regards,
Ramchandra
From India, Kolhapur
Dear Ram Chandra,
OHSAS requirements for training program are as follows:
1. Employee Training:
i) Effects of noise
ii) Hearing protection
iii) Audiometric test
iv) Measuring noise
2. Exposure monitoring
3. Audiometric test
4. Employee follow-up
5. Record-keeping
6. Noise control
7. Hearing Protection Devices
To measure noise:
- Dosimeter: A body-worn instrument that measures and stores sound over time, which can be read later
- Engineering Surveys: Require sophisticated acoustical equipment that registers dB level, frequency, and intensity of noise from machinery
Audiometric Test: To be conducted within 6 months of the first exposure to critical levels. It measures the softest sound you can hear at each test frequency.
Noise monitoring by Dosimeter is carried out by the environmental department in our plant. Audiometric tests are conducted by doctors, and Engineering Surveys can be performed by the Safety Department.
Seniors, I am looking forward to hearing your views as well.
Regards,
Hansa Vyas
From India, Udaipur
OHSAS requirements for training program are as follows:
1. Employee Training:
i) Effects of noise
ii) Hearing protection
iii) Audiometric test
iv) Measuring noise
2. Exposure monitoring
3. Audiometric test
4. Employee follow-up
5. Record-keeping
6. Noise control
7. Hearing Protection Devices
To measure noise:
- Dosimeter: A body-worn instrument that measures and stores sound over time, which can be read later
- Engineering Surveys: Require sophisticated acoustical equipment that registers dB level, frequency, and intensity of noise from machinery
Audiometric Test: To be conducted within 6 months of the first exposure to critical levels. It measures the softest sound you can hear at each test frequency.
Noise monitoring by Dosimeter is carried out by the environmental department in our plant. Audiometric tests are conducted by doctors, and Engineering Surveys can be performed by the Safety Department.
Seniors, I am looking forward to hearing your views as well.
Regards,
Hansa Vyas
From India, Udaipur
Dear Hansa,
Thank you very much for your quick response. I would like to add some points from my side.
OSHA TRAINING REQUIREMENT 1910.95(i)(4):
(4) The employer shall provide training in the use and care of all hearing protectors provided to employees.
(1) The employer shall institute a training program for all employees who are exposed to noise at or above an 8-hour time-weighted average of 85 decibels and shall ensure employee participation in such a program.
(2) The training program shall be repeated annually for each employee included in the hearing conservation program. Information provided in the training program shall be updated to be consistent with changes in protective equipment and work processes.
(3) The employer shall ensure that each employee is informed of the following:
(i) The effects of noise on hearing;
(ii) The purpose of hearing protectors, the advantages, disadvantages, and attenuation of various types, and instructions on selection, fitting, use, and care; and
(iii) The purpose of audiometric testing and an explanation of the test procedures.
Dear seniors/all,
I have one question: Is a safety trainer required to have any special certification to conduct training programs? If yes, what type of certification is required? If no, who is the competent person to conduct training (safety dept/HR dept...)?
Thanks in advance.
From United States, Fpo
Thank you very much for your quick response. I would like to add some points from my side.
OSHA TRAINING REQUIREMENT 1910.95(i)(4):
(4) The employer shall provide training in the use and care of all hearing protectors provided to employees.
(1) The employer shall institute a training program for all employees who are exposed to noise at or above an 8-hour time-weighted average of 85 decibels and shall ensure employee participation in such a program.
(2) The training program shall be repeated annually for each employee included in the hearing conservation program. Information provided in the training program shall be updated to be consistent with changes in protective equipment and work processes.
(3) The employer shall ensure that each employee is informed of the following:
(i) The effects of noise on hearing;
(ii) The purpose of hearing protectors, the advantages, disadvantages, and attenuation of various types, and instructions on selection, fitting, use, and care; and
(iii) The purpose of audiometric testing and an explanation of the test procedures.
Dear seniors/all,
I have one question: Is a safety trainer required to have any special certification to conduct training programs? If yes, what type of certification is required? If no, who is the competent person to conduct training (safety dept/HR dept...)?
Thanks in advance.
From United States, Fpo
Dear Seniors, Thank you for your valuable inputs on this thread. Now, I would like to know how to evaluate the ear muffs or ear plugs as per international standards, if available. (Reusable or disposable? Which will be the best in the industry?) I am eagerly waiting for your inputs.
Regards, Saudagar Bhossale
From Czech Republic, Mlada Boleslav
Regards, Saudagar Bhossale
From Czech Republic, Mlada Boleslav
The Origin and Impact of Noise
The word "noise" is derived from the Latin term 'nausea'. Noise is a type of atmospheric pollution in the form of waves. It is a shadowy public enemy that has increased in the modern age of industrialization and technological advancement.
Definitions of Noise
Many industrial psychologists and environmentalists have defined the term noise:
1. Harrell defines noise as 'an unwanted sound which increases fatigue and, under some industrial conditions, causes deafness'.
2. According to Environmental Health criteria, 'noise is considered any unwanted sound that may adversely affect the health and well-being of individuals or the population'.
What is Sound?
Physically, sound is a mechanical disturbance propagated as a wave motion in air and other elastic or mechanical media such as water or steel. Physiologically, it is an auditory sensation evoked by this physical phenomenon (fact of occurrence).
The human ear is very sensitive to sound waves of frequency 20 Hertz (unit of frequency, one cycle per second) to 2000 Hz pitch, but not all sounds are detectable by the human ear. There are two types of sounds:
1. Ultra Sound
Ultra sound is sound in which the frequency range exceeds approximately 15 Hz. It is beyond the upper limit of normal hearing, meaning it has a frequency too high to excite the sensation of hearing.
2. Intra Sound
Intra sound is sound below a frequency of about 16 Hz. It is below the lower limit of normal hearing and is commonly referred to as vibration.
With Regards,
Rohan Puthran
From India, Karamsad
The word "noise" is derived from the Latin term 'nausea'. Noise is a type of atmospheric pollution in the form of waves. It is a shadowy public enemy that has increased in the modern age of industrialization and technological advancement.
Definitions of Noise
Many industrial psychologists and environmentalists have defined the term noise:
1. Harrell defines noise as 'an unwanted sound which increases fatigue and, under some industrial conditions, causes deafness'.
2. According to Environmental Health criteria, 'noise is considered any unwanted sound that may adversely affect the health and well-being of individuals or the population'.
What is Sound?
Physically, sound is a mechanical disturbance propagated as a wave motion in air and other elastic or mechanical media such as water or steel. Physiologically, it is an auditory sensation evoked by this physical phenomenon (fact of occurrence).
The human ear is very sensitive to sound waves of frequency 20 Hertz (unit of frequency, one cycle per second) to 2000 Hz pitch, but not all sounds are detectable by the human ear. There are two types of sounds:
1. Ultra Sound
Ultra sound is sound in which the frequency range exceeds approximately 15 Hz. It is beyond the upper limit of normal hearing, meaning it has a frequency too high to excite the sensation of hearing.
2. Intra Sound
Intra sound is sound below a frequency of about 16 Hz. It is below the lower limit of normal hearing and is commonly referred to as vibration.
With Regards,
Rohan Puthran
From India, Karamsad
Evaluating Ear Muffs and Ear Plugs
I also have the same query: how to evaluate ear muffs or ear plugs according to international standards, if available? (Reusable or Disposable) Which option would be the best in the industry?
Thanks in advance for your help.
Regards,
Ramchandra
From India, Kolhapur
I also have the same query: how to evaluate ear muffs or ear plugs according to international standards, if available? (Reusable or Disposable) Which option would be the best in the industry?
Thanks in advance for your help.
Regards,
Ramchandra
From India, Kolhapur
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