Noise

Introduction/Background

Noise is not a new hazard. It has been a constant threat since the industrial revolution. Too much noise exposure may cause a temporary change in hearing or a temporary ringing in your ears. These short-term problems usually go away within a few minutes or hours after leaving the noise. However, repeated exposures to loud noise can lead to permanent, incurable hearing loss or tinnitus.

It is important to have a complete understanding of the auditory hazards present on your operation. Auditory hazards are anything that a worker or animal may be exposed to that results in unsafe and harmful conditions within an environment, specifically, the pork production environment. While exposure to auditory hazards can result in mild to severe consequences for agricultural workers, the goal should always be to prevent them completely, or at the very least minimize their effects. Unfortunately, hearing damage could be irreversible and, depending on the intensity, duration and frequency of hazardous exposure could be untreatable.

On swine farms, noise levels may easily exceed 95 decibels during feeding time and bleeding of hogs. Nose levels up to 110-115 decibels have been recorded. The OSHA limit in general industry for noise exposure is to 90 decibels over an eight hour work shift. Other examples of hazardous noise areas in pork operations can occur during blood collection, breeding, feeding, processing baby pigs, running large machinery, and power washing.

Complying With OSHA’s Hearing Conservation Amendment
CFR 1910.95: A Brief Overview

Do I Need a Hearing Conservation Program?

If you have asked yourself this question, the answer is probably yes! OSHA requires an
“effective, on-going hearing conservation program” if sound levels on your operation are at or above an 8-hour time-weighted average sound level (TWA) of 85 decibels measured on the A scale (slow response) or, equivalently, a dose of fifty percent.. For purposes of the hearing conservation program, employee noise exposures shall be computed in accordance with appendix A and Table G-16a , and without regard to any attenuation provided by the use of personal protective equipment.

According to Safe Farm at Iowa State University, you may also want to consider a program and hearing protective devices if:

• You or your employees experience "ringing" in the ears after being in a noisy area;
• You or your employees are bothered, nervous, or anxious after being in a noisy area;
• You or your employees want to increase your comfort;
• You or your employees are unusually fatigued after working in a noisy area, or
• A doctor recommends one.

Compliance with CFR 1910.95, the federal Hearing Conservation Amendment, involves, but
is not limited to, the following steps:

1. Assess Risk of Exposure – Noise exposure monitoring, or noise measurement, is required to determine which workers are at risk for excessive exposure to noise. Monitoring shall be repeated whenever there is a change in production, process, equipment or controls that increases noise exposure.

2. Test Hearing – Each worker in the Hearing Conservation Program (HCP) must get an original audiogram, called a baseline, within six months of starting work in a HCP area to determine how well he/she hears before he or she is exposed to noise by this employer.

3. Hearing Protection – Employer shall make hearing protectors available to all employees exposed to an 8-hour time-weighted average of 85 decibels or greater at no cost to employees. It’s the employer’s responsibility to make sure that Hearing Protective Devices are used appropriately.

4. Training and Education – Workers in the HCP receive annual training in the effects of
noise on hearing, aspects of Hearing Protective Device use (including purpose, use, care, applicability, advantages, selection, fitting, and noise reduction values), the purpose for testing hearing, and explanation of the testing procedure. Training also allows workers to ask any questions they have about noise and hearing.

5. Noise Controls – The Hearing Conservation Amendment requires the implementation of feasible engineering and/or administrative controls, as well as mandatory hearing protection, where exposures exceed a time weighted average of 90 dBA. Efforts should focus on feasible engineering controls to reduce exposure to noise.

(SOURCE: information for this section was obtained from the National Hearing Conservation Association‘s Guide #4: A Practical Guide to Complying with OSHA’s Hearing Conservation Amendment CFR 1910.95 http://www.hearingconservation.org/docs/Prac_Guide4.pdf and the Council for Accreditation in Occupational Hearing Conservation – CAOHC – Spring 1998 Update). Please Note: This information does not constitute an exhaustive explanation of how to implement a Hearing Conservation Program, but is meant to be an overview. Please consult an expert to assist you in setting an OSHA regulated program. See the SOURCES OF EXPERT ASSISTANCE at the end of this section for more information.

Hazard

It is important to have a complete understanding of the auditory hazards present on your operation. Auditory hazards are anything that a worker or animal may be exposed to that results in unsafe and harmful conditions within an environment, specifically, the pork production environment. While exposure to auditory hazards can result in mild to severe consequences for agricultural workers, the goal should always be to prevent them completely, or at the very least minimize their effects. Unfortunately, hearing damage could be irreversible and, depending on the intensity, duration and frequency of hazardous exposure could be untreatable.

Challenge: Your employees may be exposed to hazardous noise levels each day. They may
believe that because they have become accustomed to a noise and it doesn’t seem to bother them they do not need hearing protection.

Solution: Educate employees about auditory hazards and the effects of hearing loss. Explain that just because a noise does not bother them, does not mean that damage is not occurring. Often the progression of hearing loss takes time and the signs of loss go undetected until the damage is severe. Provide employees training on auditory safety and prevention and make available personal protective equipment, such as earplugs or muffs. Make sure the employees are trained on their proper usage. *(Refer to the section on PERSONAL PROTECTIVE EQUIPMENT FOR AUDITORY HEALTH AND SAFETY.)

Challenge: Noise induced hearing loss is usually a gradual, difficult to detect injury. How can I tell if an employee has suffered from hearing loss?

Solution: Three tests can be conducted:

1. Noise surveys: Hazardous levels of noise can be detected by a trained professional using sound level meters. Avoid excessive noise levels for 14 hours before the test;

2. Hearing tests: A local medical facility can perform a hearing test;

3. Self tests: Listen. If a ringing or buzzing sound is present after working with noisy equipment, overexposure to noise has probably occurred. (Source: Institute of Agricultural Medicine and Occupational Health)

Remember: Impress upon your employees the critical importance of adherence to an auditory health and safety program for the preservation of their hearing. Provide the appropriate PPE, as well as training.

Identify the Hazard Zones

The first step toward auditory health and safety is to identify the source or cause of a hazard. A hazard zone for hearing occurs during any phase of production when noise levels are at or above 85 decibels. To accurately identify the hazard zones on your operation, measure decibel levels at different times and at different locations on your farm. How quickly hearing loss takes place depends on the intensity of the noise, its duration, and how often the exposure occurs.

How can employers determine if employees are in a hazard zone?

Have employees follow this simple rule: If you have to shout to be heard by someone three feet from you, you are probably in a hazard zone (the noise is probably greater than 85 dB) and need to wear hearing protection to prevent damage. If sounds seem muffled or softer after noise exposure or you are experiencing a ringing, buzzing or whistling in your ear, you have probably damaged hearing ability. Repeated exposure can result in permanent, untreatable hearing damage.

Common examples of hazard zone areas in pork operations are during:

• blood collection
• breeding
• feeding
• processing baby pigs
• running large machinery
• power washing

Remember: You can’t prevent hazardous noise exposure if you don’t know when and where in your operation noise levels are dangerous…KNOWING THE SOURCE or CAUSE is first step toward hearing safety.

Prevention

Now that you have identified the sources or causes of potentially hazardous exposures for
hearing, work toward understanding the basic steps in prevention and then consistently apply the preventive steps. Set an example with your employees for hearing health and safety through common sense prevention. While it is never too late to put safe hearing steps into place on your operation, the time for implementation of these steps is before damage occurs, rather than after. The goal should be to reduce or completely eliminate the hazard. However, if you are still at risk, preventive measures must be properly implemented for protection. The chart below will help you identify how long you can be exposed to a certain level of noise (measured in decibels or dB) before damage occurs.

How can I reduce the level of noise on my operation?

• Reduce the noise at the source. For example, noise reduction of a power washer could occur by placing the motor in another room or outside.
• If possible, remove yourself and employees from a hazard zone during the times and situations when noise levels are excessive.
• Achieve noise filtration by properly wearing hearing personal protective equipment such as earplugs or earmuffs.

Remember: Preventing hazardous noise exposure relies on you and our employees taking proactive, rather than reactive measures toward health and safety.

Personal Protective Equipment (PPE) for Hearing Health and Safety

Personal Protective Equipment (PPE) is a vitally important line of defense against hazards. You need to provide the PPE your employees may need to guard them against hazards on the job.

• Hearing protection should be provided to employees free of charge and it is your responsibility that they know how to properly use it.
• This may require extra effort for employees with special needs such as non-English speakers.
• Hearing protective devices (HPDs) come in many shapes, sizes and protection levels.
• Knowing how you intend on using the HPDs will help match your needs to the appropriate device.
• Many hearing protective devices will have labeled Noise Reduction Ratings (NRRs) that indicate the level of protection they provide.
• These numbers are based on optimized lab testing and bear little resemblance to actual protection among employees in real life work environments.
• The National Hearing Conservation Association recommends using these ratings not as a buying guide, but as an indicator that a device has been designed and tested for noise reduction.

There are three basic types of hearing protective devices:
Foam Ear Plugs
Ear Muffs
Semi-aural Devices

FAQs

Employer FAQs
Q: How many days per year would an employee have to be exposed to an environment with noise levels in excess of the 85 decibel before he/she is required to be covered by the company's hearing conservation program?

Q: Once in the program, how long does an employee have to go without being exposed to 85 dB to be removed from the program?

Q: If an employee has been in an HCP, experienced a standard threshold shift (STS) and then, at a later time, changed jobs to an area where they are no longer in the program, are there any continuing obligations under the program with regard to this employee?

Employee FAQs
Q: Can you poke out your eardrums with earplugs?

Q: We work in a dusty, dirty place. Should I worry that our ears will get infected by using earplugs?

Q: Can you hear warning sounds, such as backup beeps, when wearing hearing protectors?

Q: Won't hearing protectors interfere with our ability to hear important sounds our machinery and equipment make?

Q: Will we be able to hear each other talk when wearing hearing protectors?

Q: How long does it take to get used to hearing protectors?

Q: How long can someone be in a loud noise before it's hazardous?

Q: How can I tell if a noise situation is too loud?

Q: How often should your hearing be tested?

Q: I already have hearing loss and wear a hearing aid, hearing prevention programs don't apply to me, right?

Q: At first, the noise levels during certain pork production activities seemed quite loud, but now I am used to the noise. Do I still need to wear hearing protection?

Q: Is there any way I can tell if I have started losing my hearing before the damage is severe?

Q: Sometimes I hear a ringing in my ears. What does that mean?

Q: Can’t I just get a hearing aid if I lose my hearing?

Q: Where can I get a hearing test?

Q: Where can I get information about ringing in my ears?

Q: How many days per year would an employee have to be exposed to an environment with noise levels in excess of the 85 decibel (dB) time weighted average (TWA) before he/she is required to be covered by the company's hearing conservation program (HCP) (i.e., one day, ten days, thirty days)?

Q: How many days per year would an employee have to be exposed to an environment with noise levels in excess of the 85 decibel before he/she is required to be covered by the company's hearing conservation program?

A: One day. The occupational noise exposure standard requires that all employees exposed to noise levels at or above 85 dB on an 8-hour (TWA) must be included in a HCP. This includes employees who may have only occasional exposures at this level. For example, the HCP provisions would apply with respect to an engineer or other such employees who visit a facility several times a year and are exposed to TWA noise levels at or above 85 dB, even though they may not experience any other such exposures during the year.

When enforcing the standard, OSHA reviews employer records and may perform personal monitoring to determine if all employees with exposures equaling or exceeding the TWA of 85 dB have been included in the HCP.[back to top of FAQs]

Q: Once in the program, how long does an employee have to go without being exposed to 85 dB to be removed from the program?

A: Employees who have not been exposed to noise levels equal to or exceeding 85 dB (as an 8-hour TWA) for an entire year following their last annual audiogram may be removed from the program.[back to top of FAQs]

Q: If an employee has been in an HCP, experienced a standard threshold shift (STS) and then, at a later time, changed jobs to an area where they are no longer in the program, are there any continuing obligations under the program with regard to this employee?

A: In such a situation, employers would be required to comply with the provisions detailed in 1910.95(m). This paragraph requires the employer to retain noise exposure measurements relating to the employee for two years and to retain audiometric test records for the duration of the affected employee's employment.[back to top of FAQs]

Q: Can you poke out your eardrums with earplugs?

A: That is unlikely for two reasons. First, the average ear canal is about 1 1/4 inches long. The typical ear plug is between 1/2 to 3/4 of an inch long. So even if you inserted the entire earplug, it would still not touch the eardrum. Second, the path from the opening of the ear canal to the eardrum is not straight. In fact, it is quite irregular. This prevents you from poking objects into the eardrum.[back to top of FAQs]

Q: We work in a dusty, dirty place. Should I worry that our ears will get infected by using earplugs

A: Using earplugs will not cause an infection. But use common sense. Have clean hands when using earplugs that need to be rolled or formed with your fingers in order for you to insert them. If this is inconvenient, there are plenty of earplugs that are pre-molded or that have stems so that you can insert them without having to touch the part that goes into the ear canal.[back to top of FAQs]

Q: Can you hear warning sounds, such as backup beeps, when wearing hearing protectors?

A: The fact is that there are fatal injuries because people do not hear warning sounds. However, this is usually because the background noise was too high or because the person had severe hearing loss, not because someone was wearing hearing protectors. Using hearing protectors will bring both the noise and the warning sound down equally. So if the warning sound is audible without the hearing protector, it will usually be audible when wearing the hearing protector. For the unusual situations where this is not the case, the solution may be as simple as using a different hearing protector. Also, many warning systems can be adjusted or changed so warning signals are easier to detect.[back to top of FAQs]

Q: Won't hearing protectors interfere with our ability to hear important sounds our machinery and equipment make?

A: Hearing protectors will lower the noise level of your equipment; it won't eliminate it. However, some hearing protectors will reduce certain frequencies more than others; so wearing them can make noises sound different. In cases where it's important that the sound just be quieter without any other changes, there are hearing protectors that can provide flat attenuation.
There are also noise-activated hearing protectors that allow normal sounds to pass through the ear and only "turn-on" when the noise reaches hazardous levels. There are even protectors that professional concert musicians use that can lower the sound level while retaining sound fidelity.[back to top of FAQs]

Q: Will we be able to hear each other talk when wearing hearing protectors?

A: Some people find they can wear hearing protectors and still understand speech. Others will have trouble hearing speech while wearing hearing protectors. Being able to hear what other people say depends on many things: distance from the speaker, ability to see the speaker's face, general familiarity with the topic, level of background noise, and whether or not one has an existing hearing impairment. In some cases, wearing hearing protectors can make it easier to understand speech.
In other instances, people may be using hearing protectors to keep out too much sound. You may need a protector that reduces the sound enough to be safe without reducing the sound too much to hear speech at a comfortably loud level. For those people who work in noise and must communicate, it may also be necessary to use communication headsets. Allow your employees to try different protectors. Some will work better than others at helping them to hear speech, and different protectors may work better for different people.[back to top of FAQs]

Q: How long does it take to get used to hearing protectors?

A: Think about getting a new pair of shoes. Some shoes take no time to get used to. Others - even though they are the right size - can take a while to get used to. Hearing protectors are no different from other safety equipment in terms of getting used to them. But if hearing protectors are the wrong size, or are worn out, they will not be comfortable. Also, workers may need more than one kind of protector at their job. For example, no one would wear golf shoes to go bowling. If hearing protectors are not suitable for the work being done, they probably won't feel comfortable.[back to top of FAQs]

Q: How long can someone be in a loud noise before it's hazardous?
A: The degree of hearing hazard is related to both the level of the noise as well as to the duration of the exposure. But this question is like asking how long can people look at the sun without damaging their eyes. The safest thing to do is to ensure workers always protect their ears by wearing hearing protectors anytime they are around loud noise.

Q: How can I tell if a noise situation is too loud?
A: There are two rules: First, if you have to raise your voice to talk to someone who is an arm's length away, then the noise is likely to be hazardous. Second, if your ears are ringing or sounds seem dull or flat after leaving a noisy place, then you probably were expose to hazardous noise.

Q: How often should your hearing be tested?
A: Anyone regularly exposed to hazardous noise should have an annual hearing test. Also, anyone who notices a change in his/her hearing (or who develops tinnitus) should have his or her ears checked. People who have healthy ears and who are not exposed to hazardous noise should get a hearing test every three years.

Q: Since I already have hearing loss and wear a hearing aid, hearing prevention programs don't apply to me, right?
A: If you have hearing loss, it's important to protect the hearing that you have left. Loud noises can continue to damage your hearing making it even more difficult to communicate at work and with your family and friends.

Q: At first, the noise levels during certain pork production activities seemed quite loud, but now I am used to the noise. Do I still need to wear hearing protection?
A: Yes. Even though a noise doesn’t seem to be bothering you, that doesn’t mean that damage is not occurring. Very often, a family member or co-worker will be the first to notice that a person is losing his or her hearing. Hearing loss often takes time and you might not notice it until the damage is severe. Remember that once you start losing your hearing, it’s irreversible. Wearing hearing protection whenever you are around loud noise will help prevent further damage.

Q: Is there any way I can tell if I have started losing my hearing before the damage is severe?
A: The best way to tell is to see a certified audiologist, a specialist in hearing loss. Potentially hazardous noise levels in the environment can be detected by a trained person who uses a sound level meter. Also, if you have to raise your voice to be heard by a person just an arm’s length away, the noise around you is likely loud enough to damage your hearing.

Q: Sometimes I hear a ringing in my ears. What does that mean?
A: That ringing in the ears is called tinnitus. Many people who have noise-induced hearing loss also experience ringing, hissing, roaring, whistling, chirping or even clicking sounds in their ears. This may show up before you notice any hearing loss. If you’re experiencing signs of tinnitus, be sure to see a doctor, to help determine whether you have noise-induced hearing loss.

Q: Can’t I just get a hearing aid if I lose my hearing?
A: Sure you can, but the problem is that while a hearing aid will amplify sounds, it won’t reverse any damage that has already been done. Also, don’t think that it’s just older people who experience hearing loss. If you regularly work around loud equipment or machinery or around squealing pigs and haven’t been wearing hearing protection, hearing loss may have already begun.

Links

Noise and Hearing Loss Prevention (NIOSH). Includes sections on how to choose a hearing protection device, a link to the hearing protection compendium (searchable to find HPDs by criteria), a searchable database of power tool noise emissions, and more.

OSHA Occupational Noise Exposure Standard. If you want to read the specifics.

OSHA Occupational Noise Exposure Standard and interpretations.

Noise Exposure and Hearing Loss (CDC). Basic background information.

Hearing conservation checklist for employers (CDC)