Noise Exposure At Work - Washington State

Noise Exposure at WorkHearing Loss Prevention Rule (Noise)WAC 296-817Developed by the Division of OccupationalSafety & Health (DOSH) for employee trainingMeeting DOSH Training RequirementsThis training module gives basic information on noiseas outlined in the Hearing Loss Prevention Rule – WAC296-817.To meet the DOSH training requirements for HearingLoss Prevention, you must include information specificto your worksite as indicated in slides #15, 16, 29, 41and 42.Preview this program and include your specificworkplace information prior to conducting the training.It is recommended you keep an attendance roster foryour records to document training.NoiseExposureExposure AtNoiseat WorkWorkThis presentation will cover the following topics:The effects of noise onhearing,Hearing protection – theirpurpose, types and use,The purpose of audiometrictesting and how it works,Your right to see noisemeasurement records andhearing test results.11

Effects of exposure to loud noiseExposure to loud noise willinevitably cause hearing lossover time.Loud noise damages or destroysthe nerves in the inner ear.Another effect can be “tinnitus”or permanent ringing in the ear.2When is Noise Too Loud?Noise is measured in units called“decibels” or “dB”If two people 3 feet apart must shoutto be heard, the background noise istoo loud (above 85 decibels). Noise above 140 decibels causes painand immediate hearing loss.3Long Term Exposure to NoiseOur ears can recover fromshort exposure to loudnoise, but over time nervedamage will occur.The longer and louder thenoise, the greater chancepermanent damage willoccur.There is really no suchthing as “tough ears” or“getting used to it”.42

Effects of noise to inner earHair cells in inner ear transmit noise signals to the brainNoise-damaged hair cellsNormal hair cells5Hearing Loss From Noise ExposureHearing loss from noiseexposure is usually notnoticed because it is sogradual.Usually a person loses theability to hear higher pitchesfirst.Often the first noticeableeffect is difficulty in hearingspeech.Normal hearingHearing loss6Tinnitus From Noise ExposureExposure to high noise levelscan also cause permanentringing in the ear or “tinnitus”.Tinnitus sufferers usuallycomplain of constant whistling,squealing, roaring or buzzing inone or both ears.Severe tinnitus may disruptsleep, reduce concentration andcause irritability and depression.73

What is Too Much Noise Exposure?Damage from noise exposuredepends on the loudness andlength of exposure.Scientific studies have shownthat hearing loss can occurwhen 8-hour average noiseexposure exceeds 85 decibels.8What is Too Much Noise Exposure?The risk of hearing lossincreases dramatically as noiselevels increase.Exposure to noise levels above115 decibels for even fiveminutes is very risky.Photo by Kenny Mitchell in Creative CommonsImpact or banging noise above140 decibels will causeimmediate damage to nervesin the ear.9Daily Allowable Exposure Times to NoiseThe table below shows noise levels and how long aperson can be exposed without hearing protectionbefore there is damage to the ear.Noise LevelAllowable Exposure Time85 decibels8 hours90 decibels4 hours100 decibels1 hour105 decibels30 minutes110 decibels15 minutes115 decibels0 minutes104

11Examples of Noisy EquipmentEquipmentBack HoeChain SawFront-end LoaderGunshotJackhammerLawn MowerTractorCircular SawNoise Level85-95 decibels110 decibels90-95 decibels140 decibels112 decibels90 decibels95-105 decibels90-100 decibelsPhoto by Bri in Creative Commons12Noisy areas & equipment at our companyList or discuss your noisy equipment andnoise sources and their noise levels here.135

Noise controls we use in our workplaceList equipment or methods you have used toreduce noise levels to employees – enclosures,barriers, mufflers, noise absorbing materials,etc. and/or the use of hearing protection.14Types of Hearing ProtectionThere are three types ofhearing protection – ear muffs,earplugs and ear caps.Ear muffs and earplugs provideabout equal protection, earcaps somewhat less.earmuffsearplugs15ear capsTypes of Hearing ProtectorsAll hearing protectors aredesigned to reduce the intensity(loudness) of noise to the innerear.They work much better thanwads of cotton or bits of clothstuffed in the ear.All three types have advantagesCotton doesn’tand disadvantages and peoplework!!vary on which they prefer touse.166

Hearing Protection – Ear PlugsEarplugs are made of foam,rubber or plastic and are eitherone-size-fits-all or in sizessmall, medium and large.Some are disposable, some arereusable.They are lightweight, andrequire no maintenance.They are inserted into the earcanal.17Ear Plug ComfortSome people may find earplugs uncomfortable to wearfor long periods at first.Ear plugs rarely cause infectionor prolonged irritation of theear canal.Most people can find acomfortable fit by tryingseveral different sizes, types orbrands.Custom-molded earplugs canbe obtained for maximumcomfort.custom moldedearplugs18Inserting Foam EarplugsFoam type earplugs are one-size-fits-all andmust be inserted properly into the ear.Roll earplug into small cylinder first, then insert in ear.197

Inserting Foam EarplugsEarplug incorrectly insertedEarplug correctly inserted20Ear MuffsEar muffs cover the wholeear and are preferred bysome people.They have replaceablepads and some high-techstyles filter out specificnoise pitches.They last longer than mostplugs.21Attached EarmuffsSome muffs are attached tohard hats or goggles.Some high-tech muffs canfilter out certain frequenciesor have radios inside forcommunication in high noiseareas.228

Ear Muff Comfort & GlassesMuffs can be uncomfortablein hot weather.Muffs don’t seal well forsomeone with glasses orheavy sideburns.23Ear CapsEar caps are likeearplugs, except theydo not go into the earcanal, they only block it.They are good foroccasional use or forpeople who findearplugs uncomfortable.They are not asprotective as earplugsor muffs.24Noise Reduction of Hearing ProtectionThe “noise reductionrating” or “NRR” ofhearing protection ismeasured in decibels.The NRR is found onthe earmuff or earplugpackage. The higherthe number, thegreater the protection.259

NRR ExampleGrinder noise level – 95 decibels26Hearing Protection Available at our CompanyInsert the list of hearing protection used at yourcompany here.Alternatively, you can simply show the actual hearingprotection you provide your employees. Include NRRrating of each and when or where hearing protection isneeded or required.27How can you hear anythingwith earmuffs on?Using earmuffs or plugs innoisy areas can actuallymake it easier to hearcoworkers or machinery.They reduce overwhelmingloud background noise.They are similar to darkglasses that reduce thesun’s glare making it easierto see.2810

Proper Use of Hearing ProtectionEarmuffs and plugsprovide good protectiononly when usedproperly.Sometimes people willremove hearingprotection for “just aminute” in a noisy area.In areas of very highnoise exposure, thiscould result in noiseoverexposure.It won’t protect your ears ifit is around your neck!!!29Proper Use of Hearing ProtectionIt takes just a few minutesof unprotected exposure atnoise above 115 decibelsto risk hearing damage.Earplugs not well insertedinto the ear canal will notprovide completeprotection.Likewise, earmuffs notsnug against the head will“leak” noise into the ear.30Hearing Aids Are Not Hearing ProtectionHearing aids do not block outenough sound for mostworkplace noise.Some hearing aids canactually increase the noiselevel at the ear.Just turning off the hearingaids will not prevent furtherhearing loss from noiseexposure.Photo by Birmingham Museum in Creative Commons3111

Portable Radios/CD Players/iPodsMost of these devices do notprovide protection from noise.The earphones are notearmuffs and the music onlyadds to background othernoise.The music level in theearphones themselves canexceed 85 decibels and causehearing loss.Photo by Ron Lute in Creative Commons32What is Audiometric Testing?“Audiometric testing” isthe same thing as hearingtests.It is done by trainedtechnicians to detect anyhearing loss.Audiometric testing isrequired by DOSH for anyemployees exposed toexcessive noise.33Purpose of Audiometric TestingMost of us develop a mildhearing loss as we age,especially in the higherpitches.A severe or significanthearing loss at a youngerage may mean you have hadexcessive noise exposure.Audiometric testing doneyearly can detect earlystages of hearing loss.Photo by Montse PB in Creative Commons3412

Audiometric TestingAudiometric testing resultscan be used to check thefollowing:If the hearing protectionin use is adequate,If there is a change innoise exposure,If there is a medicalcondition of the earunrelated to noiseexposure.Photo by World Bank in Creative Commons35How Does Audiometric Testing Work?When you are firsthired, a baseline test istaken.The testing is repeatedevery year after thatand compared to thebaseline test result.If a hearing loss isdetected, we will ask thedoctor or audiologistwhat is the cause.36Audiometric TestingAudiometric testing producesprinted audiograms whichshow hearing ability atseveral pitches orfrequencies.These frequencies includethose of the human voice.The second and followingyear tests are compared tothe first year tests orbaseline.3713

What is an Audiogram?An audiogram is a printed chart of the results of thehearing test. They look similar to the results below.Normal hearingSevere hearing loss38Noise measurement records &hearing test resultsYou have the right to see noisemeasurement records and get copiesof your hearing test results.Show here where noise records and/oraudiometric testing results are kept or giveemployees copies of these records.39Noise AuditsDescribe your noise auditing program here, if you do it.Hearing protection audits are a tool for use inevaluating your hearing loss prevention program incases where audiometric testing doesn't provide auseful measure.4014

Noise QuizThe following questions are optional. They can beused to check employee’s understanding of thistraining and promote discussion. You can addmore questions for a short written or verbal quiz.Question 1What happens when people are exposedto excessive noise?a) They can’t hear someone talking to them.b) Over a period of time, they will develophearing loss.c) Some people may develop permanent ringingin their ears.d) Some people will be stressed out by constantexposure to loud noise.Question 2What is the lowest level of noise that cancause hearing loss?a) When it hurts your ears.b) 65 decibelsc)85 decibelsd)An average of 85 decibels over 8 hours.15

Question 3What is NRR?a) The noise level of rifles.b) The noise rating of any loud machinery.c) The noise reduction rating of hearing protection.d) A measure of how well earplugs work.Question 4Ear plugs work better than ear muffs inblocking out noise.a) True.b) False.c) It depends.Question 5Why is audiometric testing required?a) To make sure you haven’t gone deaf.b) To test for any hearing loss during youremployment.c) To test the noise of machinery.d) To see how well you remember noise trainingmaterial.16

Noise above 140 decibels causes pain and immediate hearing loss. 3 Long Term Exposure to Noise Our ears can recover from short exposure to loud noise, but over time nerve damage will occur. The longer and louder the noise, the greater chance permanent damage will occur. There is really no such thing as “tough ears” or “getting used to it”. 4. 3 Effects of noise to inner ear Normal .