Noise-Induced Hearing Loss

Learn about how the provisions of noise-induced hearing loss regulations, published under the Occupational Health and Safety Act (South Africa), AFFECT THE DIVING INDUSTRY.
The noise-induced hearing loss (NIHL) regulations apply in all workplaces where a person at work may be exposed to a noise level above 85 A-weighted decibels (dB[A]). Such a noise level is determined by evaluating the exposure over a period of eight hours. Therefore, if a person is exposed to high noise levels for short durations, the average exposure over eight hours may well be below the noise rating limit. The way in which such exposure is determined in practice is by means of a specific measurement by an approved inspection authority.
For details on approved inspection authorities who may perform noise measurements, visit http://www.labour.gov.za/DOL/downloads/documents/useful-documents/occupational-health-and-safety/aiapamphlet.pdf
The noise-induced hearing loss (NIHL) regulations apply in all workplaces where a person at work may be exposed to a noise level above 85 A-weighted decibels (dB[A]). Such a noise level is determined by evaluating the exposure over a period of eight hours. Therefore, if a person is exposed to high noise levels for short durations, the average exposure over eight hours may well be below the noise rating limit. The way in which such exposure is determined in practice is by means of a specific measurement by an approved inspection authority.
For details on approved inspection authorities who may perform noise measurements, visit http://www.labour.gov.za/DOL/downloads/documents/useful-documents/occupational-health-and-safety/aiapamphlet.pdf
ASSESSMENT OF EXPOSURE
The regulations require an employer to formally assess the workplace for potential exposure above the noise rating level of 85 dB(A) at least once every two years. Such an assessment should consider the potential sources of noise and the extent to which persons may be exposed. Other factors to include in the assessment would be the work processes and whether failure of noise control measures can be expected.
In terms of the diving environment, the following are common sources of loud noises:
Whenever the assessment by the employer determines that a person may be exposed above the noise rating limit, formal measurements and monitoring of noise exposure are required. The details of the noise monitoring required are described in the regulations, including references to the South African Bureau of Standards (SABS) documents that prescribe certain standards. The noise monitoring may only be performed by an approved inspection authority and this must also be performed every two years.
The records of assessments of potential exposure and of formal noise monitoring must be kept for a period of 40 years.
NOISE ZONES
All areas with noise levels above the noise rating limit must be clearly demarcated with signs indicating that the area is a noise zone. No person may be allowed to enter such an area without wearing appropriate hearing protection. In addition, attempts should be made to reduce the noise levels by means of engineering or administrative control measures (e.g. the rotation of workers).
MEDICAL SURVEILLANCE
Persons who are exposed to noise levels above 85 dB(A) are required to take part in a medical surveillance programme, which will screen them for possible effects of exposure to noise. This would include the performance of a number of different audiogrammes (at baseline, followed by regular periodical audiogrammes as prescribed and exit audiogrammes). Not just any medical person may perform the medical surveillance – the regulations specifically state that it must be performed by someone with a qualification in occupational health; an ear, nose and throat (ENT) specialist; or an audiometrist. The records of the medical surveillance must also be kept for a period of 40 years.
TRAINING
All persons who are required to work in a noise zone are required to receive training on aspects related to the noisy work. The contents of the training (as listed in the regulations) include the contents of the regulations; the sources of noise exposure; the health effects and safety risks associated with noise; precautions to be taken by the workers (including how to wear and maintain hearing protective devices and the limitations to their use); the need for medical surveillance; and how to report problems. Additional aspects that form part of the training would be related to a number of duties and responsibilities the regulations place on workers.
SOME PRACTICALITIES
Although noise exposure could be measured with relative ease both above and below water, the negative effects of underwater exposures are a bit more difficult to predict or model. Even exposures at levels exceeding 85 dB underwater may not always lead to hearing loss due to various dampening factors. This includes splinting of the tympanic membrane by water; the increased density of gas in the middle ear space (depending on the depth of the dive); and the gas mixture (i.e. gas mixtures other than air such as heliox or trimix used by recreational or commercial divers), all of which will have an effect on the auditory perception of the diver. These factors make it exceedingly difficult to model a noise dose-response curve in this environment. An additional complication is that occlusive earplugs are incompatible with diving, so that personal hearing protection strategies are not available to divers. This leaves engineering and administrative measures as the only practical options.
Notwithstanding the difficulty in modelling noise exposure of or providing personal hearing protection for divers, typical patterns of NIHL are frequently identified in divers (especially working divers). Accordingly, as we stated in the previous article in this series, some of them may qualify for compensation.
In conclusion, all diving operators and employers of divers should formally conduct a noise risk assessment as prescribed in the regulations and take further action (noise monitoring, medical surveillance, etc.) if noise exposure above the legislated limit is present.
REFERENCES
The regulations require an employer to formally assess the workplace for potential exposure above the noise rating level of 85 dB(A) at least once every two years. Such an assessment should consider the potential sources of noise and the extent to which persons may be exposed. Other factors to include in the assessment would be the work processes and whether failure of noise control measures can be expected.
In terms of the diving environment, the following are common sources of loud noises:
- Compressor rooms are notorious for their high levels of noise and cylinder filling stations may likewise be noisy.
- Depending on the machinery used and the activities performed, workshops can be quite noisy.
- The air flow into hyperbaric chambers from high pressure gas banks have been measured as exceeding 100 dB(A).
- The peak noise levels that are measured in diver helmets (especially the free-flow type used for diving in contaminated waters) have been measured to exceed 110 dB(A).
- Commercial divers may be exposed to a range of noisy underwater tools where levels exceeding 170 dB have been measured.
- Boat engines may also cause noise exposure above the exposure limit.
Whenever the assessment by the employer determines that a person may be exposed above the noise rating limit, formal measurements and monitoring of noise exposure are required. The details of the noise monitoring required are described in the regulations, including references to the South African Bureau of Standards (SABS) documents that prescribe certain standards. The noise monitoring may only be performed by an approved inspection authority and this must also be performed every two years.
The records of assessments of potential exposure and of formal noise monitoring must be kept for a period of 40 years.
NOISE ZONES
All areas with noise levels above the noise rating limit must be clearly demarcated with signs indicating that the area is a noise zone. No person may be allowed to enter such an area without wearing appropriate hearing protection. In addition, attempts should be made to reduce the noise levels by means of engineering or administrative control measures (e.g. the rotation of workers).
MEDICAL SURVEILLANCE
Persons who are exposed to noise levels above 85 dB(A) are required to take part in a medical surveillance programme, which will screen them for possible effects of exposure to noise. This would include the performance of a number of different audiogrammes (at baseline, followed by regular periodical audiogrammes as prescribed and exit audiogrammes). Not just any medical person may perform the medical surveillance – the regulations specifically state that it must be performed by someone with a qualification in occupational health; an ear, nose and throat (ENT) specialist; or an audiometrist. The records of the medical surveillance must also be kept for a period of 40 years.
TRAINING
All persons who are required to work in a noise zone are required to receive training on aspects related to the noisy work. The contents of the training (as listed in the regulations) include the contents of the regulations; the sources of noise exposure; the health effects and safety risks associated with noise; precautions to be taken by the workers (including how to wear and maintain hearing protective devices and the limitations to their use); the need for medical surveillance; and how to report problems. Additional aspects that form part of the training would be related to a number of duties and responsibilities the regulations place on workers.
SOME PRACTICALITIES
Although noise exposure could be measured with relative ease both above and below water, the negative effects of underwater exposures are a bit more difficult to predict or model. Even exposures at levels exceeding 85 dB underwater may not always lead to hearing loss due to various dampening factors. This includes splinting of the tympanic membrane by water; the increased density of gas in the middle ear space (depending on the depth of the dive); and the gas mixture (i.e. gas mixtures other than air such as heliox or trimix used by recreational or commercial divers), all of which will have an effect on the auditory perception of the diver. These factors make it exceedingly difficult to model a noise dose-response curve in this environment. An additional complication is that occlusive earplugs are incompatible with diving, so that personal hearing protection strategies are not available to divers. This leaves engineering and administrative measures as the only practical options.
Notwithstanding the difficulty in modelling noise exposure of or providing personal hearing protection for divers, typical patterns of NIHL are frequently identified in divers (especially working divers). Accordingly, as we stated in the previous article in this series, some of them may qualify for compensation.
In conclusion, all diving operators and employers of divers should formally conduct a noise risk assessment as prescribed in the regulations and take further action (noise monitoring, medical surveillance, etc.) if noise exposure above the legislated limit is present.
REFERENCES
- The Noise Induced Hearing Loss Regulations, published under section 43 of the Occupational Health and Safety Act, 1993.
- Goplen, F.K., Aasen, T., Grønning, M., Molvær, O.I. & Nordahl, S.H. Hearing loss in divers: a 6-year prospective study. Eur Arch Otorhinolaryngol; 2011 Jul; 268(7): p979-85.
- Skogstad, M., Haldorsen, T., Arnesen, A.R. & Kjuus, H. Hearing thresholds among young professional divers: a 6-year longitudinal study. Aviat Space Environ Med.; 2005 Apr; 76(4): p366-9.
- Skogstad, M., Eriksen, T. & Skare, Ø. A twelve-year longitudinal study of hearing thresholds among professional divers. Undersea Hyperb Med.; 2009 Jan-Feb; 36(1): p25-31.
- Talmi, Y.P. Barotrauma-induced hearing loss. Scand Audiol; 1991; 20(1): 1-9.
- Molvaer, O.I. & Lehmann, E.H. Hearing acuity in professional divers. Undersea Biomed Res.; 1985; 12(3): p333-349.
- Molvaer, O.I. & Albrektsen, G. Hearing deterioration in professional divers: an epidemiologic study. Undersea Biomed Res.; 1990 May; 17(3): p231-46.
- Curley, M.D. & Knafelc, M.E. Evaluation of noise within the MK 12 SSDS helmet and its effect on divers’ hearing. Undersea Biomed Res.; 1987 May; 14(3): p187-204.
- Summitt, J.K. & Reimers, S.D. Noise: A hazard to divers and hyperbaric chamber personnel. Aerosp Med.; 1971 Nov; 42(11): p1173-7.
- Ross, J.A., Macdiarmid, J.I., Dick, F.D. & Watt, S.J. Hearing symptoms and audiometry in professional divers and offshore workers. Occup Med (Lond).; 2010 Jan; 60(1): p36-42.
- Smith, P.F. Toward a standard for hearing conservation for underwater and hyperbaric environments. J Aud Res.; 1985 Oct; 25(4): p221-38.
- Molvaer, O.I. & Gjestland, T. Hearing damage risk to divers operating noisy tools underwater. Scand J Work Environ Health; 1981 Dec; 7(4): p263-70.
- Hughes, K.B. Sensorineural deafness due to compression chamber noise. J Laryngol Otol.; 1976 May 1; 90(8): p803-7.
Posted in Alert Diver Spring Editions
Categories
2020
January
February
Group Fitness at the PoolHow to Rescue a Distressed diver at the SurfaceHow to manage Near-DrowningNo Sit-ups no problem How to manage MalariaHow to manage Oxygen Deficiency (Hypoxia)What to do when confronted by a sharkHow to manage Scombroid PoisoningHow to perform a Deep Diver RescueHow to perform One-rescuer CPRHow to perform a Neurological Assessment
March
DAN’s Quick Guide to Properly Disinfecting Dive GearCOVID-19 : Prevention Recommendations for our Diving CommunityGermophobia? - Just give it a reasonable thoughtScuba Equipment care – Rinsing and cleaning diving equipmentCOVID-19 and DAN MembershipFurther limitations imposed on travels and considerations on diving activitiesDAN Membership COVID-19 FAQsLancet COVID-19 South African Testing SitesCOVID-19 No Panic Help GuideGetting Decompression Sickness while FreedivingDown in the DumpsCardiovascular Disease and DivingDelayed Off-GassingDiving after Dental surgeryDiving with Multiple MedicationsPygmy Seahorses: Life AquaticAfrica DustCOVID-19 Myth BustersScuba Units Are Not Suitable Substitutes for VentilatorsDisinfection of Scuba Equipment and COVID-19Physioball Stability Exercises
April
COVID-19 AdvisoryScuba Equipment Care - Drying & Storing Your GearTransporting Diving Lights & BatteriesHow to Pivot Your Message During a CrisisTourism Relief FundCOVID-19 Business Support ReviewDiving After COVID-19: What We Know TodayEUBS-ECHM Position Statement on Diving ActivitiesPart 2: COVID-19 Business Support ReviewPress Release
May
Diving in the Era of COVID-19Dive Operations and COVID-19: Prepping for ReturnCOVID-19 & Diving Activities: 10 Safety RecommendationsCOVID-19: Surface Survival TimesThe Philippines at its FinestThe Logistics of ExplorationThe Art of the Underwater SelfieShooter: Douglas SeifertFAQs Answered: Disinfecting Scuba EquipmentStock your First-Aid KitResearch and OutreachCovid-19 ResearchOut of the BlueEffects of Aspirin on DivingThe New Pointy end of DivingDiving and Hepatitis CCaissons, Compressed-Air work and Deep TunnellingPreparing to Dive in the New NormalNew Health Declaration Form Sample Addressing C-19 IssuesDiving After COVID 19: What Divers Need to Know
June
Travel Smarter: PRE-TRIP VACCINATIONSAttention-Deficit/Hyperactivity Disorder and DivingCOVID-19: Updated First Aid Training Recommendations From DANDiving with a Purpose in National Marine SanctuariesStay Positive Through the PandemicFor the Dive Operator: How to Protect Your Staff & ClientsStudying Deep reefs and Deep diversAsking the Right QuestionsLung squeeze under cold diving conditions
July
Dive DeprivationVolunteer Fish Surveys: Engage DiversDAN Member Profile: Mehgan Heaney-GrierTravel Smarter: Don’t Cancel, Reschedule InsteadDive Boat Fire SafetyRay of HopePartner ExercisesDiving at AltitudeAluminium ExposureHip FracturesAcoustic NeuromaGuidelines for Lifelong Medical Fitness to DiveNew Dive Medical Forms
August
Women in Diving: Lauren Arthur, Conservationist & Natural History Story TellerWomen in Diving: Dr Sara Andreotti White Shark ResearcherTiming ExerciseWomen in Diving: The Salty Wanderer, Charlie WarlandWomen in Diving: Beth Neale, Aqua soul of freedivingWomen in Diving: Diving and spearfishing Diva, Jean HattinghWomen in Diving: Zandile Ndhlovu, The Black Mermaid
September
October
Freediving For ScienceStep Exercises with CardioFluorescence Imaging help Identify Coral BleachingChildren and DivingThe Watchman device and divingScuba Diving and Factor V Leiden gene mutationNitrogen Narcosis at shallow depthsOil and Particulates: Safe levels in Breathing Air at depthDive Principles for Coping with COVID-19The Importance of a Predive Safety CheckTalya Davidoff: the 'Plattelandse Meisie' Freediver
2019
February
April
May
DAN Press ReleaseYour Dive Computer: Tips and tricks - PART 1Your Dive Computer: Tips and tricks - PART 2Aural HygieneDCS AheadHow Divers Can Help with coral conservationRed Tide and shellfish poisoningDiving after Kidney DonationDiving with hypertrophic cardiomyopathyEmergency Underwater Oxygen Recompression
June
July
September
October
November
Exercise drills with DowelsHeart-rate TrainingCultivating ConservationTRavel Smarter : Evaluating an unfamiliar Dive operatorChallenging the Frontiers of Decompression ResearchTravel Smarter: Plan for Medical EmergenciesWhen should I call my Doctor?DAN Student Medical Expense CoverageAdvice, Support and a LifelineWetsuits and heat stressDiving after Chiropractic adjustments
2018
April
Flying after pool diving FAQLung squeeze while freediving FAQDiving after Bariatric surgery FAQMarine injuries FAQVasovagal Syncope unpredictable FAQIncident report procedure FAQDiving after knee surgery FAQDiving when in RemissionDive with orbital Implant FAQInert gas washout FAQOxygen ears FAQPost Decompression sicknessChildren and diving. The real concerns.Diving after SurgeryPhysiology of Decompresssion sickness FAQDiving and regular exerciseGordon Hiles - I am an Underwater Cameraman and Film MakerScuba Air QualityBreath-hold diving. Part 3: The Science Bit!Compensation Legislation and the Recreational DiverCape Town DivingFive pro tips for capturing better images in cold waterThe Boat Left Without You: Now What?
May
When things go wrongEmergency Planning: Why Do We Need It?Breath-hold diving: Running on reserve -Part 5 Learning to RebreatheSweet Dreams: When Can I Resume Diving Post Anaesthesia?Investing in the future of reefsTo lie or not to lie?THE STORY OF A RASH AFTER A DIVEFirst Aid KitsTaravana: Fact or Falacy?
June
Oxygen Unit MaintenanceKnow Your Oxygen-Delivery Masks 1Know Your Oxygen-Delivery Masks 2Emergency Oxygen unitsInjuries due to exposure - HypothermiaInjuries due to exposure - Altitude sicknessInjuries due to Exposure - Dehydration and other concernsHow to plan for your dive tripThe Future of Dive MedicinePlastic is Killing our ocean
September
Return to DivingDiagnoses: Pulmonary blebSide effects of Rectogesic ointmentDiving with ChemotherapyReplacing dive computers and BCDsCustomize Your First-Aid KitPlan for medical emergenciesHow the dive Reflex protects the brain and heartDry suits and skin BendsAltitude sickness and DCSScuba Diving and Life Expectancy
2017
March
April
Incident Insight: TriageA Field Guide to Minor MishapsSnorkels: Pros & ConsTime & RecoveryMedication & Drug UseDiving with CancerNitrox FAQCOPD FAQHyperbaric Chamber FAQJet Lag FAQHydration FAQAnticoagulant Medication FAQFluid in the Ear FAQEye Surgery FAQElderly Divers FAQNitrogen FAQHealth Concerns FAQMotion Sickness FAQMicronuclei FAQ
June
August
2016
February
March
Breath-Hold Diving & ScubaReturn to Diving After DCITiming Exercise & DivingHot Tubs After DivingSubcutaneous EmphysemaIn-Water RecompressionDiving at AltitudeFlying After DivingDiving After FlyingThe Risks of Diabetes & DivingFlu-like Symptoms Following a DiveHand & Foot EdemaFrontal HeadachesBladder DiscomfortLatex AllergiesRemember to BreatheProper Position for Emergency CareAches & PainsCell Phones While DrivingSurfers Ear Ear Ventilation TubesDealing with Ear ProblemsDiving with Existing Ear InjuriesPerforated Ear DrumENT SurgeryUnpluggedCochlear ImplantsPortuguese Man-of-WarJellyfish StingsLionfish, Scorpionfish & Stonefish EnvenomationsStingray Envenomation Coral Cuts, Scrapes and RashesSpeeding & Driving Behaviour
June
Newsflash! Low Pressure Hose DeteriorationItching & rash go away & come back!7 Things we did not know about the oceanMigraine HeadacheAttention Deficit Disorder Cerebral Vascular AccidentEpilepsyCerebral PalsyHistory of SeizuresMultiple Sclerosis Head TraumaBreast Cancer & Fitness to Dive IssuesLocal Allergic ReactionsSea LiceHow ocean pollution affects humans Dive Fatality & Lobster Mini-Season StatisticsPregnancy & DivingReturn to Diving After Giving BirthBreast Implants & DivingMenstruation During Diving ActivitiesOral Birth ControlBreast FeedingPremenstrual SyndromeOsteoporosisThe Aftermath of Diving IncidentsCompensation Legislation & the Recreational DiverNoise-Induced Hearing LossLegal MattersThe Nature of Liability & DivingDAN Legal NetworkWaivers, Children & Solo DivingHealthy, but overweight!Taking Medication while Scuba DivingGetting Fit for the Dive SeasonBone Considerations in Young DiversAsthma and Scuba DivingHepatitisDiving with HyperglycemiaShoulder PainDiving After Spinal Back Surgery
August
Hazard Identification & Risk AssessmentCaring For Your People Caring For Your FacilitiesCaring For Your BusinessScuba Air Quality Part 1Scuba Air Quality Part 2Chamber Maintenance Part 1Chamber Maintenance Part 2The Aging Diver Propeller SafetyRelease The PressureDon't Get LostMore Water, Less Bubbles13 Ways to Run Out of Air & How Not To7 Mistakes Divers Make & How To Avoid ThemSafety Is In The AirHow Good Is Your Emergency Plan
2015
January
March
2 Comments
Hi , I may have missed it as I was away in China until recently, Please let me know if there have been any similar as above studies relating to "Tinnitus" and it's potential affects to divers. I have a student diver with the symptoms but could not define any negative effect under water in confined water sessions so far, and intend continuing with open water qualification. His medical hearing tests have been normal. What now?