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
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 studiesKids 9 years Adolescents 17 years
”The leisure habit study” 2005, in Göteborg, Sweden % of girls and boys who listens to music > 3 times per week Years Girls Boys 65 89
What sound levels are our children exposed to? (Freestyles CD’s & Mp3’s) L Aeq = dB (Hodgetts, Rieger & Szarko, 2007) and 110 dB A in ear canal with probe michrophone L Aeq = 80 dB (Williams, 2005) 139 dB SPL Max out 9 cd´s (Fligor & Cox 2004) dB= L Aeq (corrected för FF) +7-9 dB A with canalphones L Aeq = 97 dB (Hellström, 2001) L Aeq = 82 dB (Airo, Pekkarinen % Olkinuora, 1996) L Aeq = 83.4 dB (Rice, Breslin & Roper, 1987)
3 reference studies Noise induced threshold shift (Niskar A. et al 2001) 6-11 yrs 8.5% % Constant Tinnitus ( Widen SE, Erlandsson, 2004) yrs yrs Often/always tinnitus (K-M Holgers 2001) 9-16 yrs 16%
Pilots done, Örebro Univ. Pilot I Pilot II n=60 41 sex19 w /41 men 23 w/18 men age= 33 (SD=13.2)16 (SD= 1.5) Listening durance11 yrs4 yrs Questionnaires6041 SLM*6041 Valid measurm.4138 SLM* = Sound level measurements
Stockholm Central Station
Women N=19 % Men N=41 % Women N=23 % Men N=18 % Exposure 1 hr hr Volume setting: 25 % Pilot I N= 60 Pilot II N= 41 Mean=33 yrs Mean= 16 yrs
Pilot I N= 60 Mean=33 yrs Pilot II N= 41 Mean= 16 yrs Women N=19 % Men N=41 % Women N=23 % Men N=18 % Listens daily Sleeps with Mp “ Bad hearing ” Occlusion 629- Tinnitus Sound sensitivity Hearing fatigue Distortion --9-
Pilots done, cont. I: Stockholm Central Station, 33 yrs (n=41) average dB L Aeq,FF, 60sec = 83 ( ) average L A,FF max, 60sec = 88.5 ( ) II: Stockholm Culture House, 16 yrs (n=40) average dB L Aeq,FF, 60sec = 81.1 ( ) average L A,FF max, 60sec = 85.2 ( )
: Ongoing Study I Kids, 9 years Planned: N=500 Pure tone hearing thresholds Tests:Tympanometry Otoacoustic emissions DPOAE, SOA Questionnaire:Hearing and music listening habits
Kids, 9 yrs Some preliminary results N= % 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 ( % reference material 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.
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 thresholds Tests: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 II Adolescents 17 years, preliminary results 329 normal hearing 68 hard of hearing 60has been tested in lab (both normal hearing & hard of h 52 % 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, 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, Hopefully this fall, 2010
The team Carina Wikström – Audiologist Tobias Åslund - Sound Engineer Johannes Olsson - Sound Engineer Jenny Engelbrektsson – Audiologist Johanna Pernhall Breder – Audiologist AMMOT- 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