Portable music players- preferred sound levels and listening habits

Kim R Kähäri Ph. D, Audiologist

The Linneaus Centre HEAD and the institute for Disability Research, Örebro University

&The Inst. for Neuroscience and Physiology Göteborg University, Sweden

kim.kahari@neuro.gu.se

Structure

Background Childrens leisure time activities and sound exposure

Pilot studies done Pilot I: Stockholm Central Station 33 yrs Pilot II: Stockholm Culture House 16 yrs

Ongoing studies Kids 9 yearsAdolescents 17 years

”The leisure habit study” 2005,in Göteborg, Sweden

% of 41 754 girls and boys who listens to music > 3 times per week

Years10-15 16-18

Girls8194

Boys6589

What sound levels are our children exposed to? (Freestyles CD’s & Mp3’s)

LAeq= 83-89 dB (Hodgetts, Rieger & Szarko, 2007) and 110 dB A in ear canal with probe michrophone

LAeq= 80 dB (Williams, 2005)

139 dB SPL Max out 9 cd´s (Fligor & Cox 2004)dB= 91-121 LAeq (corrected för FF) +7-9 dB A with canalphones

LAeq= 97 dB (Hellström, 2001)

LAeq= 82 dB (Airo, Pekkarinen % Olkinuora, 1996)

LAeq= 83.4 dB (Rice, Breslin & Roper, 1987)

3 reference studies

Noise induced threshold shift (Niskar A. et al 2001)

6-11 yrs 8.5%12-19 15.5%

Constant Tinnitus (Widen SE, Erlandsson, 2004)

16-17 yrs 6.8-10.3 18-19 yrs 14.0-19.7

Often/always tinnitus (K-M Holgers 2001)

9-16 yrs 16%

Pilots done, Örebro Univ.

Pilot I Pilot IIn= 60 41sex 19 w /41 men 23 w/18 menage= 33 (SD=13.2) 16 (SD= 1.5)Listening durance 11 yrs 4 yrsQuestionnaires 60 41SLM* 60 41Valid measurm. 41 38

SLM* = Sound level measurements

Stockholm Central Station

Women N=19 %

Men N=41 %

Women N=23 %

Men N=18 %

Exposure 1 hr 42 30 35 18

2 hr 37 38 44 24

29

Volume setting: 25 %

16 7 4 -

50 21 24 36 33

75 37 44 50 44

100 21 24 9 22

Pilot I N= 60 Pilot II N= 41Mean=33 yrs Mean= 16 yrs

Pilot I N= 60Mean=33 yrs

Pilot II N= 41Mean= 16 yrs

Women N=19

%

Men N=41

%

Women N=23

%

Men N=18

%

Listens daily 53 58 74 94

Sleeps with Mp3 28 20 17 15

“Bad hearing” 22 32 26 28

Occlusion 6 2 9 -

Tinnitus 11 20 9 -

Sound sensitivity 17 10 26 -

Hearing fatigue 17 - 17 6

Distortion - - 9 -

Pilots done, cont.I: Stockholm Central Station, 33 yrs (n=41)

average dB LAeq,FF,60sec = 83 (73.4 -101.8)

average LA,FF max, 60sec = 88.5 (76.5 -107.4)

II: Stockholm Culture House, 16 yrs (n=40)average dB LAeq,FF,

60sec = 81.1 (57.9 - 99.1)

average LA,FF max, 60sec = 85.2 (63.2 -103.9)

2009-2010: Ongoing Study IKids, 9 years

Planned: N=500 Pure tone hearing thresholds

Tests: TympanometryOtoacoustic emissions DPOAE, SOA

Questionnaire: Hearing and music listening habits

Kids, 9 yrsSome preliminary results N=102

5.4% Show a SNITS*: (N=8/144 with normal compliance test)(8.5% reference material 6-11 yrs, Niskar et al 2001)

5 % have tinnitus on daily/always basis(16% often/always constant reference material 9-16 yrs, Holgers 2001(6.8-10.3% reference material 16-17 yrs, Widen, Erlandsson 2004)

62 % uses head phones/ Mp3’s when listening to music 9 % uses head phones/ Mp3’s on daily basis

*SNITS: Suspected Noise induced threshold shift.

2009-2010 Ongoing Study II Adolescents, 17 yrs.

Questionnaire: Hearing and PMP listening habits to normal hearing & young hard of hearing

A sample of 80 students to test:

Pure tone hearing thresholdsTests: Tympanometry

Otoacoustic emissions DPOAE, SOA

Questionnaires: Hearing and PMP habits /music listening Youth Attitude to Noise Scale (Widen Olsen S. 2004)

Sound level measurements: of PMP in laboratorie using KEMAR

Ongoing Study IIAdolescents 17 years, preliminary results

329 normal hearing68 hard of hearing60 has been tested in lab (both normal hearing & hard

of h52 % are frequent users (daily), most use 75% of max

volume

Typical activity when listening:Transportation (on bus, train, bicycle when walking)

Message

1) We can acknowledge the risk for future hearing damages

2) Consumer- friendly technique! Zero tolerance! Safe sound level limits, especially for childrens’ products. Spread knowledge to create awareness about risks

Noise and Health, 2010

1. Portable Music Players - Preferred Sound Levels and Listening Habits, Among Adults Kim R. Kähäri, T. Åslund, J. Olsson, 2010, submitted

2. Portable Music Players - Preferred Sound Levels and

Listening Habits, Among Adolescents Kim R. Kähäri, T. Åslund, J. Olsson, 2010, on it’s way…

3. Hopefully this fall, 20104. Hopefully this fall, 2010

The teamCarina Wikström – Audiologist

Tobias Åslund - Sound EngineerJohannes Olsson - Sound EngineerJenny Engelbrektsson – Audiologist

Johanna Pernhall Breder – AudiologistAMMOT- The Soundheroes

Acknowledgements

Prof. Claes Möller, Audiological Research Center in Örebro FAS Hearing Center/CKV Karolinska Institutet, Stockholm

The Swedish Association of Hard of Hearing People