3M OH & ES Division Current Issues in Hearing Loss Prevention Lee Hager, Hearing Conservationist 517.290.1907/lhager@mmm.com
3M OH & ES Division Where do we stand today? Hearing Loss Recordability Trend 28,400 26,900 24,400 23,000 22,100 163,100 hearing losses since 2004 19,500 18,800 220,700 215,500 203,600 183,300 165,200 146,700 138,400 2004 2005 2006 2007 2008 2009 2010 2
3M OH & ES Division What s the Story? Exposure Assessment and Limits? Resource Allotment? Training? Hearing Protectors? Probably all of the above and more 3
Exposure Assessment Percentage of employers implementing elements of hearing conservation requirements. Company Size Audiometry Monitoring Hearing Protection Small 0.0% 0.0% 16.5% Medium 5.2% 4.5% 37.9% Large 18.7% 29.5% 83.5% and yes, sadly enough, 26 year old data is the best we have NOES 1986, NIOSH 4
Exposure Limit = Acceptable Risk How much noise is OK? Exposure Level db(a) Organization 90 85 80 ISO 1975 21% 10% 0% EPA 1973 22% 12% 5% NIOSH 1972 29% 15% 3% Percent risk of material hearing loss (hearing threshold levels >= 25 db) above that anticipated in non-noise exposed population, based on 40-year working lifetime. OSHA accepted 21% to 29% excess risk in 1981 (PEL) Revised position to 10% to 15% in 1983 (Action Level) 5
Deeper Look at Damage Risk Avg Exp Level, dba ISO 1971 From NIOSH White Paper (5/2012) Selection of Audiometric Frequencies included in analysis 0.5-1-2 khz 1-2-3 khz 1-2-3-4 khz NIOSH 1972 EPA 1973 ISO 1990 NIOSH 1997 NIOSH 1972 ISO 1990 NIOSH 1997 ISO 1990 NIOSH 1997 90 21 29 22 3 23 29 14 32 17 25 85 10 15 12 1 10 16 4 14 6 8 80 0 3 5 0 4 3 0 5 1 1 More recent work identifies higher frequencies as key for verbal communication Analysis-dependant inclusion of higher frequencies increases population
Risk does not stop @ 90 or @ 85 Damage RIsk Criteria % excess risk 70 60 50 40 30 20 10 0 75* 80 85 90 95* Exposure ISO EPA NIOSH 7
Resource Allotment HCP Cost Implications 1976 Cost Impact Analysis $32 per worker - $115.36 in 2007$ $12 (37% of total) for monitoring $20 for audiometric testing 1983 HCA Cost Impact Analysis $41 per worker - $84.31 in 2007$ $12-$18 (44% of total) for monitoring $10 for hearing protection devices 1992 OSHA Philadelphia Region Compliance Guide $86.60 per worker - $126.50 in 2007$ Recent analysis for major manufacturer Automotive - $250 per noise-exposed employee per year General Industry - $350 per noise-exposed employee per year 8
Real Cost Implications Worker Compensation $9k to $150k for total loss Partial loss $0 to $? Dobie & Megerson, AIHA Noise Manual, Chapter 18 Long term health care Hearing aids for life 9
Instrumentation New Stuff Either: Real smart, or Real smart but hiding it Dan Johnsons Dream Etymotic Research Remote monitoring 10
Task-Based Exposure Assessment Modeling 11
Training or not so much Promote behavioral change Health Belief Model Behavior depends on perception of: Severity of a potential illness Susceptibility to that illness Benefits of taking preventive action Self-efficacy My actions will make a difference Barriers to taking that action 12
Our mission? Define the decibel Beat people up for offthe-job behaviors Provide nap time during workday Check the box Persuade people that hearing loss is a severe impediment to lifestyle Communicate susceptibility Communicate benefits Remove barriers Real Perceived 13
What does it sound like? Use hearing loss simulators Caution: May not be effective with workers with pre-existing hearing loss Google NIOSH HLSim to get your copy 14
How about Hearing Protectors? Intended to be last line of defense against NIHL Instead, often the ONLY protection against noise So how s that working? 15
Do HPD provide what we expect? Laboratory Field Berger, EARLog 20, 1993 16
Is it the labeling process? NRR EPA testing and labeling requirements Lab based Unreliability leads to derating OSHA: (NRR-7)/2 NIOSH: Variable by type Pressure on mfr. Label value is inaccurate Variability in even lab data Typical SD 3-5 db per frequency Test Frequency 125 250 500 1000 2000 3150 4000 6300 8000 NRR Mean 37.4 40.9 44.8 43.8 36.3 41.9 42.6 46.1 47.3 29 SD 5.7 5.0 3.3 3.6 4.9 3.0 3.1 3.5 2.7 17
Special HPD for special noises and needs Impulse Weapons fire Arc flash Low attenuation Flat attenuation 18
Communication in Noise Ambient Listening Radio Communication UHF DECT 19
Fit testing Hearing Protectors If we want to know how well HPD work on individuals, test them on individuals Technologies REAT Loudness Balance MIRE PAR Note: All of the approaches described today are point measures 20
REAT Approaches Hearing test with and without HPD Each frequency/each ear separately Existing equipment Audiometer phones Caveats Loudspeakers in test booth Gold Standard 21
FitCheck Special headphones High output High volume Pulsed 1/3 octave bands Subjective As variable as a hearing test Time consuming Background noise May be issues with HOH/tinnitus http://www.michaelassociates.com/fitcheck/fitcheck.htm 22
REAT-like Systems Subjective Threshold response Integrafit Single frequency http://www.integrafit.com/ NIOSH HPDWellFit Under development; limited frequencies QuickFit Pass/fail http://www.cdc.gov/niosh/mining/pubs/pdfs/2009-112.pdf Web-based http://www.cdc.gov/niosh/mining/topics/hearingloss/quickfitweb.htm 23
Loudness Balance Balance tones binaurally No HPD One HPD Both HPD Each frequency separately Any earplug Subjective New skill Different test tones Time consuming May be issues with HOH workers/tinnitus 24
Loudness Balance Sperian VeriPro www.howardleight.com/veripro * Single frequency quick check option 25
MIRE Simultaneous measurement inside and outside HPD yields noise reduction (NR) Specially prepared/probed HPD Software provides stimulus, calculation and compensation MIRE (objective NR) to REAT (subjective insertion loss) 26
E-A-Rfit TM Objective Quick No issues with HL Background noise Specially prepared earplug EARfit.3M.com 27 3M 2012 All Rights Reserved.
Safety Meter by Phonak Similar to EARfit Custom HPD product Port permits msmt Headphone source http://www.phonak-communications.com/en/hearingprotection/hearing-protection-products/safetymeter-fit-testing-system/ 28 3M 2012 All Rights Reserved.
What do we find when we can look? % of tests 14% 12% 10% 8% 6% 4% 2% Classic Reg Classic Regular N = 1665 NRR1979 = 29 db Mean = 30 db SD = 6.8 db 80 th = 37 db 20 th = 24 db 0% 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 PAR (db) Note: scale on all charts 1 to 50 PAR on X; % of tests 0% to 15% on Y UltraFit N = 480 NRR1979 = 25 Mean = 26 db SD = 5.5 db 80 th = 31 db 20 th = 22 db % of tests 14% 12% 10% 8% 6% 4% 2% 0% 2 4 6 8 10 12 14 16 18 UltraFit 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 3M 2010. All Rights Reserved. PAR (db)
Food Company Pilot n=168 Baseline Re-fit Training Re-fit New Plug No-Fit 5%-New Plug 6%-No Fit 18%- Training 71%- Baseline 30 3M 2010. All Rights Reserved.
Chemical Company PAR >=20 on at least two plugs 31 3M 2012 All Rights Reserved.
Consumer Products Mfr First time good Retraining Alternate HPD Total 88 37 24 149 59% 25% 16% 100% Screening Test 24 37 88 First time good Retraining Alternate HPD 32 3M 2010. All Rights Reserved.
Individual Fit Testing Applications Train and motivate employees Train the trainer Assign/select HPDs Provide standard-threshold-shift (STS) follow up Determine HPD adequacy/sufficiency Audit departments Demonstrate adequacy of training Provide documentation Berger 2006 33
How about compliance? Today s OSHA: Compliance No comment Standards No comment Alliance http://www.hearingconservation.org/docs/alliancerecommendationforfittesting_final.pdf 34
Comparability With identical octave band attenuation, different systems yield different PAR values Calculation protocols Uncertainty Freq 125 250 500 1000 2000 4000 8000 Att 11 13 12 17.5 27.5 33 22 Data and chart courtesy of Murphy, NIOSH, from NHCA 2011 35 3M 2011. All Rights Reserved.
Making Progress Hearing loss prevention is possible New technologies New approaches New attitudes as research continues Courtesy Audibel 36