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Noise-Induced Hearing Loss and Its Implications for Middle School, High School, and College Band Directors Ashley Waller.

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Presentation on theme: "Noise-Induced Hearing Loss and Its Implications for Middle School, High School, and College Band Directors Ashley Waller."— Presentation transcript:

1 Noise-Induced Hearing Loss and Its Implications for Middle School, High School, and College Band Directors Ashley Waller

2 Objective To determine the presence of excessive sound pressure levels in the classrooms of four music professors at the University of Tennessee. To determine the presence of excessive sound pressure levels in the classrooms of four music professors at the University of Tennessee. To determine the presence of excessive sound pressure levels in the classrooms of three band directors at Halls Middle School and Halls High School. To determine the presence of excessive sound pressure levels in the classrooms of three band directors at Halls Middle School and Halls High School.

3 Research Questions 1. What is the typical sound pressure level (SPL), measured in decibels (dBA), experienced by each teacher/professor in their respective teaching environments?

4 Research Questions 2. What are the maximum and minimum SPL (in decibels) experienced by each teacher/professor in their respective teaching environments?

5 Research Questions 3. What is the percentage of allowable daily noise dose experienced by each teacher/professor in their respective teaching environments in accordance with both The Occupational Health and Safety Administration (OSHA) and The National Institute for Occupational Safety and Health (NIOSH)/The American Conference of Governmental Industrial Hygienists (ACGIH) decibel exchange rates?

6 Research Questions 4. Were any of the teachers/professors exposed to sound pressure levels that exceeded the maximum allowable daily noise dose according to both OSHA and NIOSH/ACGIH scales?

7 Literature Review

8 Definition of Noise-Induced Hearing Loss (NIHL) Hearing loss caused by continuous exposure to occupational noise. Hearing loss caused by continuous exposure to occupational noise. (Sataloff and Sataloff, 1993) Permanent hearing loss caused by prolonged exposure to high levels of sound. (Williot, 1991) Permanent hearing loss caused by prolonged exposure to high levels of sound. (Williot, 1991) Irreversible and generally permanent hearing loss. (Royer, 1996) Irreversible and generally permanent hearing loss. (Royer, 1996)

9 Key Characteristics of NIHL Almost always bilateral Almost always bilateral Once the exposure is discontinued, the hearing loss does not continue to progress Once the exposure is discontinued, the hearing loss does not continue to progress Noise exposure over a long period of time is more damaging than interrupted exposure to noise. Noise exposure over a long period of time is more damaging than interrupted exposure to noise. (Owens, 2003)

10 Key Characteristics of NIHL Excessive noise exposure has the potential to destroy the hair cells of the organ of Corti. These cells do not regenerate once they have been harmed or destroyed. Excessive noise exposure has the potential to destroy the hair cells of the organ of Corti. These cells do not regenerate once they have been harmed or destroyed. Individual susceptibility Individual susceptibility (Owens, 2003)

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12 Temporary Threshold Shifts (TTS) Temporary loss of hearing due to brief exposure to excessive noise. Temporary loss of hearing due to brief exposure to excessive noise. Previous level of hearing acuity will be restored after the ear repairs itself. Previous level of hearing acuity will be restored after the ear repairs itself. (Royer, 1996)

13 Permanent Threshold Shift (PTS) Permanent loss of hearing due to exposure to excessive noise. Permanent loss of hearing due to exposure to excessive noise. (Royer, 1996)

14 Decibel Levels Points of Reference 10 dB - Normal breathing 10 dB - Normal breathing 30 dB - Soft whisper 30 dB - Soft whisper 60-85 dB - Vacuum cleaner 60-85 dB - Vacuum cleaner 90 dB - Tractor/Lawn mower 90 dB - Tractor/Lawn mower 110 dB - Leaf blower/Chain saw 110 dB - Leaf blower/Chain saw 120 dB - Ambulance siren 120 dB - Ambulance siren 125 dB - Causes pain 125 dB - Causes pain 140 dB - Loudest recommended exposure WITH hearing protection. 140 dB - Loudest recommended exposure WITH hearing protection. 150 dB - Firecracker 150 dB - Firecracker 180 dB - Rocket launching from pad 180 dB - Rocket launching from pad Decibel levels of 180 dB cause death of hearing tissue.

15 Industrial Regulation of Noise Exposure Occupational Health and Safety Administration (OSHA): the maximum daily noise exposure level should not exceed 90 decibels (dBA) over an eight- hour period. Occupational Health and Safety Administration (OSHA): the maximum daily noise exposure level should not exceed 90 decibels (dBA) over an eight- hour period. A 5-dBA exchange rate is followed. A 5-dBA exchange rate is followed. (Behar, MacDonald, Lee, Cui, Kunov, & Wong, 1981)

16 OSHA Maximum Exposure Levels Duration (hours/day) Sound Pressure Level (dBA) 890 495 2100 1105 1/2110 1/4115

17 Industrial Regulation of Noise Exposure The National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH): the maximum daily noise exposure level should not exceed 85 dBA over an eight-hour period. The National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH): the maximum daily noise exposure level should not exceed 85 dBA over an eight-hour period. A 3-dBA exchange rate is followed. A 3-dBA exchange rate is followed. (Behar, MacDonald, Lee, Cui, Kunov, & Wong, 1981)

18 NIOSH/ACGIH Maximum Exposure Levels Duration (hours/day) Sound Pressure Level (dBA) 885 488 291 194 ½ (30 min)97 1/4 (15 min)100 1/8 (7.5 min)103

19 OSHA vs. NIOSH/ACGIH According to OSHA, you can stand in an environment that is at 100 decibels safely for 2 hours (120 minutes) According to OSHA, you can stand in an environment that is at 100 decibels safely for 2 hours (120 minutes) According to NIOSH/ACGIH, you can only stand in an environment that is at 100 decibels for 15 minutes. Any exposure that lasts more than 15 minutes will cause damage. According to NIOSH/ACGIH, you can only stand in an environment that is at 100 decibels for 15 minutes. Any exposure that lasts more than 15 minutes will cause damage.

20 Instances of NIHL in Music Teachers Cutietta, Millin, Royse (1989): Cutietta, Millin, Royse (1989): studied 32 high school band directors studied 32 high school band directors 41% of the band directors displayed some signs of NIHL 41% of the band directors displayed some signs of NIHL

21 Instances of NIHL in Music Teachers Cutietta, Klich, Royse, & Rainbolt (1994): Cutietta, Klich, Royse, & Rainbolt (1994): compared audiograms of 104 music educators of different genres (choral/general music, elementary instrumental, and high school instrumental) compared audiograms of 104 music educators of different genres (choral/general music, elementary instrumental, and high school instrumental) 20% of the vocal general subjects, 9 % of the elementary instrumental subjects, and 21% of the high school instrumental subjects displayed some NIHL. 20% of the vocal general subjects, 9 % of the elementary instrumental subjects, and 21% of the high school instrumental subjects displayed some NIHL. Additionally, the high school instrumental subjects displayed a pattern of increasingly greater hearing loss as age increased. Additionally, the high school instrumental subjects displayed a pattern of increasingly greater hearing loss as age increased.

22 Sound Pressure Levels Experienced By Music Teachers Royer (1996): Royer (1996): 50 sound pressure readings were taken in 23 different high school band rooms. 50 sound pressure readings were taken in 23 different high school band rooms. The average sound pressure level (SPL) was 86.7 dBA. The average sound pressure level (SPL) was 86.7 dBA. The sound pressure levels ranged from 77.8 dBA to 94.7 dBA. The sound pressure levels ranged from 77.8 dBA to 94.7 dBA. The 86.7 dBA average exceeded the NIOSH/ACGIH regulations of allowable noise exposure. The 86.7 dBA average exceeded the NIOSH/ACGIH regulations of allowable noise exposure.

23 Sound Pressure Levels Experienced By Music Teachers Owens (2003): Owens (2003): Sampled sound pressure levels in 10 Colorado high school band rooms (63 SPL readings) Sampled sound pressure levels in 10 Colorado high school band rooms (63 SPL readings) 60% of the subjects experienced sound pressure levels at or exceeding 90 dBA. 60% of the subjects experienced sound pressure levels at or exceeding 90 dBA. All were exposed to sound pressure levels at or exceeding 85 dBA. All were exposed to sound pressure levels at or exceeding 85 dBA. Maximum daily noise dosages: Maximum daily noise dosages: OSHA standards: 69.2% OSHA standards: 69.2% NIOSH/ACGIH standards: 369.3% NIOSH/ACGIH standards: 369.3%

24 Sound Pressure Levels Experienced By Music Teachers Behar et al. (2004): Behar et al. (2004): 18 Canadian public school teachers were surveyed. 18 Canadian public school teachers were surveyed. 78% of SPL readings exceeded the 85-dBA limit. 78% of SPL readings exceeded the 85-dBA limit. The average SPL experienced by the band directors was 90.5, yielding a safe exposure time of only 2.1 hours (according to NIOSH/ACGIH). The average SPL experienced by the band directors was 90.5, yielding a safe exposure time of only 2.1 hours (according to NIOSH/ACGIH).

25 Current Study

26 Materials and Methods

27 Subjects Four professors from The University of Tennessee School of Music Four professors from The University of Tennessee School of Music Professor A: Associate Director of bands, director of the Concert Band, and professor of brass methods Professor A: Associate Director of bands, director of the Concert Band, and professor of brass methods Professor B: Assistant Director of bands, director of the Symphonic Band, and professor of undergraduate conducting and woodwind methods Professor B: Assistant Director of bands, director of the Symphonic Band, and professor of undergraduate conducting and woodwind methods Professor C: Applied Trumpet professor and director of the Trumpet Ensemble Professor C: Applied Trumpet professor and director of the Trumpet Ensemble Professor D: Applied Bassoon professor Professor D: Applied Bassoon professor

28 Subjects Three band directors from Halls High School and Halls Middle School. Three band directors from Halls High School and Halls Middle School. Director A: Director of Bands at Halls High School. Director A: Director of Bands at Halls High School. Director B: Assistant Director of Bands at Halls High School and Halls Middle School. Director B: Assistant Director of Bands at Halls High School and Halls Middle School. Director C: Director of Bands at Halls Middle School. Director C: Director of Bands at Halls Middle School.

29 Equipment Brüel & Kjær Integrating Impulse Sound Level Meter, Type 2226 (manufactured by the Brüel & Kjær Company, headquartered in Nærum, Denmark) Brüel & Kjær Integrating Impulse Sound Level Meter, Type 2226 (manufactured by the Brüel & Kjær Company, headquartered in Nærum, Denmark) Calibrated using a Quest Electronics CA-22 calibrator Calibrated using a Quest Electronics CA-22 calibrator

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31 Method Two recording sessions were held for each subjects class/private lesson. Two recording sessions were held for each subjects class/private lesson. Recordings were taken at random during each session (yielding 10-16 SPL recordings per class/private lesson). An average SPL was then calculated for each class/lesson. Recordings were taken at random during each session (yielding 10-16 SPL recordings per class/private lesson). An average SPL was then calculated for each class/lesson. Sound level meter was placed next to each directors ear, approximately one to two feet behind the subject. Sound level meter was placed next to each directors ear, approximately one to two feet behind the subject.

32 Recording Sessions at the University of Tennessee Concert Band Concert Band Symphonic Band Symphonic Band Brass Methods II Brass Methods II Conducting II Conducting II Woodwind Methods II Woodwind Methods II Trumpet Ensemble Trumpet Ensemble Trumpet Lessons (Professor C) Trumpet Lessons (Professor C) Bassoon Lessons (Professor D) Bassoon Lessons (Professor D)

33 Recording Sessions at Halls Middle School and Halls High School Two 6 th Grade classes Two 6 th Grade classes Two 7 th Grade classes Two 7 th Grade classes Two 8 th Grade classes Two 8 th Grade classes HHS Concert Band class HHS Concert Band class HHS Symphonic Band class HHS Symphonic Band class HHS Indoor Drumline rehearsal (applies to Director C only) HHS Indoor Drumline rehearsal (applies to Director C only)

34 Results

35 Typical Sound Pressure Levels What is the typical sound pressure level (SPL), measured in decibels (dBA), experienced by each teacher/professor in their respective teaching environments? What is the typical sound pressure level (SPL), measured in decibels (dBA), experienced by each teacher/professor in their respective teaching environments?

36 Typical Sound Pressure Levels Professor A: Professor A: 82.8 dBAConcert Band rehearsals 90.5 dBABrass Methods classes Professor B: 92.0 dBASymphonic Band rehearsals 79.4 dBAConducting classes 81.5 dBAWoodwind Methods classes Professor C: 93.8 dBATrumpet Ensemble rehearsals 88.3 dBAPrivate lessons Professor D: 79.2 dBAPrivate lessons

37 Typical Sound Pressure Levels (UTK) 50% of the typical sound pressure levels exceeded NIOSH/ACGIH maximum SPL of 85 dBA 50% of the typical sound pressure levels exceeded NIOSH/ACGIH maximum SPL of 85 dBA 100% of the high school band directors experienced sound pressure levels at or exceeding 85 dBA (Owens, 2003) 100% of the high school band directors experienced sound pressure levels at or exceeding 85 dBA (Owens, 2003) 78% of the sound pressure levels exceeded the 85 dBA limit (Behar et al., 2004) 78% of the sound pressure levels exceeded the 85 dBA limit (Behar et al., 2004)

38 Typical Sound Pressure Levels (Halls) 6A: 89.1 dBA 6A: 89.1 dBA 6B: 88.2 dBA 6B: 88.2 dBA 7A: 87.0 dBA 7A: 87.0 dBA 7B: 89.9 dBA 7B: 89.9 dBA 8A: 87.9 dBA 8A: 87.9 dBA 8B: 85.8 dBA 8B: 85.8 dBA Concert Band: 87.9 dBA Concert Band: 87.9 dBA Symphonic Band: 89.9 dBA Symphonic Band: 89.9 dBA Indoor Drumline: 95.6 dBA Indoor Drumline: 95.6 dBA

39 Typical Sound Pressure Levels 100% of the typical sound pressure levels exceeded NIOSH/ACGIH maximum SPL of 85 dBA 100% of the typical sound pressure levels exceeded NIOSH/ACGIH maximum SPL of 85 dBA 100% of the high school band directors experienced sound pressure levels at or exceeding 85 dBA (Owens, 2003) 100% of the high school band directors experienced sound pressure levels at or exceeding 85 dBA (Owens, 2003) 78% of the sound pressure levels exceeded the 85 dBA limit (Behar et al., 2004) 78% of the sound pressure levels exceeded the 85 dBA limit (Behar et al., 2004)

40 Maximum and Minimum Sound Pressure Levels What was the maximum and minimum SPL (in decibels) experienced by each teacher/professor in their respective teaching environments? What was the maximum and minimum SPL (in decibels) experienced by each teacher/professor in their respective teaching environments?

41 Maximum and Minimum Sound Pressure Levels (UTK) Professor A: Professor A: 96.5 dBA; 54.5 dBAConcert Band 89.0 dBA; 62.0 dBABrass Methods Professor B: 97.0 dBA; 79.0 dBASymphonic Band 86.0 dBA; 70.0 dBAConducting 92.0 dBA; 63.5 dBAWoodwind Methods Professor C: 96.5 dBA; 90.5 dBATrumpet Ensemble 94.5 dBA; 83.0 dBAPrivate lessons Professor D: 83.0 dBA; 62.5 dBAPrivate lessons

42 Maximum and Minimum Sound Pressure Levels (Halls) 6A: 93.5 dBA; 79.5 dBA 6A: 93.5 dBA; 79.5 dBA 6B: 91.0 dBA; 82.5 dBA 6B: 91.0 dBA; 82.5 dBA 7A: 90.0 dBA; 83.0 dBA 7A: 90.0 dBA; 83.0 dBA 7B: 93.5 dBA; 83.0 dBA 7B: 93.5 dBA; 83.0 dBA 8A: 91.0 dBA; 82.0 dBA 8A: 91.0 dBA; 82.0 dBA 8B: 91.0 dBA; 64.0 dBA 8B: 91.0 dBA; 64.0 dBA Concert Band: 92.5 dBA; 66.5 dBA Concert Band: 92.5 dBA; 66.5 dBA Symphonic Band: 95.5 dBA; 53.5 dBA Symphonic Band: 95.5 dBA; 53.5 dBA Indoor Drumline: 101.5 dBA; 57.5 dBA Indoor Drumline: 101.5 dBA; 57.5 dBA

43 Overall Maximum and Minimum SPL (UTK) Maximum: 97.0 dBA Maximum: 97.0 dBA Minimum: 54.5 dBA Minimum: 54.5 dBA Royer 1996: Royer 1996: 94.7 dBA; 77.8 dBA 94.7 dBA; 77.8 dBA

44 Overall Maximum and Minimum SPL (Halls) Maximum: 101.5 dBA Maximum: 101.5 dBA Minimum: 53.5 dBA Minimum: 53.5 dBA Royer 1996 Royer 1996 94.7 dBA; 77.8 dBA 94.7 dBA; 77.8 dBA

45 Percent Daily Noise Dose What is the percentage of allowable daily noise dose experienced by each teacher/professor in their respective teaching environments in accordance with both OSHA and NIOSH/ACGIH decibel exchange rates? What is the percentage of allowable daily noise dose experienced by each teacher/professor in their respective teaching environments in accordance with both OSHA and NIOSH/ACGIH decibel exchange rates?

46 Percent Daily Noise Dose OSHA (UTK)

47 Percent Daily Noise Dose NIOSH/ACGIH (UTK)

48 Professor C Daily Noise Dose (Trumpet Ensemble) OSHA vs. NIOSH/ACGIH

49 Percent Daily Noise Dose OSHA (Halls)

50 Percent Daily Noise Dose NIOSH/ACGIH (Halls)

51 Director B (Indoor Drumline) Daily Noise Dose OSHA vs. NIOSH/ACGIH

52 Sound Pressure Levels in Excess of Regulations Did any of the teachers/professors experience sound pressure levels that exceeded the maximum allowable daily noise dose according to both OSHA and NIOSH/ACGIH scales? Did any of the teachers/professors experience sound pressure levels that exceeded the maximum allowable daily noise dose according to both OSHA and NIOSH/ACGIH scales?

53 Sound Pressure Levels in Excess of Regulations (UTK) Only Professor C (Applied Trumpet/Trumpet Ensemble) experienced sound pressure levels that exceeded the maximum allowable dosage. Only Professor C (Applied Trumpet/Trumpet Ensemble) experienced sound pressure levels that exceeded the maximum allowable dosage. Trumpet Ensemble rehearsals: Trumpet Ensemble rehearsals: 119.36% (NIOSH/ACGIH) 119.36% (NIOSH/ACGIH) 26.46% (OSHA) 26.46% (OSHA) During one 75-minute rehearsal, Professor C receives 19.36% more noise exposure than is safely allowed (according to NIOSH/ACGIH). During one 75-minute rehearsal, Professor C receives 19.36% more noise exposure than is safely allowed (according to NIOSH/ACGIH).

54 Sound Pressure Levels in Excess of Regulations (Halls) Hypothetical Situations

55 Hypothetical Case #1 Director X teaches only Concert Band and Symphonic Band Director X teaches only Concert Band and Symphonic Band Percent Daily Noise Dosage experienced by Director X: Percent Daily Noise Dosage experienced by Director X: 16% (OSHA) 16% (OSHA) 47% (NIOSH/ACGIH) 47% (NIOSH/ACGIH)

56 Hypothetical Case #2 Director X teaches all middle school and high school bands, as well as Indoor Drumline (twice per week) Director X teaches all middle school and high school bands, as well as Indoor Drumline (twice per week) Percent Daily Noise Dosage experienced by Director X: Percent Daily Noise Dosage experienced by Director X: 78% (OSHA) 78% (OSHA) 272% (NIOSH/ACGIH) 272% (NIOSH/ACGIH)

57 Hypothetical Case #3 Director X teaches only the middle school ensembles Director X teaches only the middle school ensembles Percent Daily Noise Dosage experienced by Director X: Percent Daily Noise Dosage experienced by Director X: 42% (OSHA) 42% (OSHA) 117% (NIOSH/ACGIH) 117% (NIOSH/ACGIH)

58 Sound Pressure Levels in Excess of Regulations Director B experiences sound pressure levels that exceed the maximum allowable dosage during Indoor Drumline rehearsals (twice per week). Director B experiences sound pressure levels that exceed the maximum allowable dosage during Indoor Drumline rehearsals (twice per week). Indoor Drumline rehearsals: Indoor Drumline rehearsals: 108.0% (NIOSH/ACGIH) 108.0% (NIOSH/ACGIH) 20.0% (OSHA) 20.0% (OSHA) During one 120-minute rehearsal, Director B receives 8.0% more noise exposure than is safely allowed (according to NIOSH/ACGIH). During one 120-minute rehearsal, Director B receives 8.0% more noise exposure than is safely allowed (according to NIOSH/ACGIH).

59 Conclusions

60 1. None of the teachers/professors experienced an SPL in excess of the OSHA 90-dBA limit, and therefore none were at risk for NIHL based upon the OSHA standard.

61 2. Four the teachers/professors displayed a significant percent daily noise dose based upon the NIOSH/ACGIH 85-dBA limit. Professor C: 119.36% for Trumpet Ensemble Professor C: 119.36% for Trumpet Ensemble Professor B: 52.30% for Symphonic Band Professor B: 52.30% for Symphonic Band Director B: 108.0% for Indoor Drumline Director B: 108.0% for Indoor Drumline Director X: 117.0% (teaching all middle school classes) Director X: 117.0% (teaching all middle school classes)

62 3. The discrepancy between the maximum noise exposure scales of OSHA and NIOSH/ACGIH signifies a need for standardization of industry noise exposure regulations.

63 So what can we do as teachers to protect ourselves?

64 Protective Equipment: Earplugs Single-Use Earplugs Single-Use Earplugs Polyurethane Foam Polyurethane Foam Inexpensive Inexpensive Available at most drugstores/major retailers (ex. Walgreens, Wal-Mart, etc.) Available at most drugstores/major retailers (ex. Walgreens, Wal-Mart, etc.)

65 Protective Equipment: Earplugs Multiple-Use Earplugs Multiple-Use Earplugs Can be washed and reused multiple times. Can be washed and reused multiple times. Usually made of rubber or silicon. Usually made of rubber or silicon. Cost: Up to $15.00 Cost: Up to $15.00

66 Protective Equipment: Earplugs Custom molded earplugs Custom molded earplugs Allow for less distortion of sound than disposable/other reusable earplugs. Allow for less distortion of sound than disposable/other reusable earplugs. Contain filters that reduce decibel levels by several decibels (ex. 9, 15, 25 dB) Contain filters that reduce decibel levels by several decibels (ex. 9, 15, 25 dB) Must be fitted by a hearing care professional Must be fitted by a hearing care professional Knox-Sevier Hearing Service Knox-Sevier Hearing Service

67 Rehearsal Room Design Evaluate your rehearsal space for proper acoustical treatment. Evaluate your rehearsal space for proper acoustical treatment. Use materials in order to absorb excess sound Use materials in order to absorb excess sound Heavy draperies/curtains: Hang these over whiteboards or concrete walls Heavy draperies/curtains: Hang these over whiteboards or concrete walls Carpet Carpet Three-dimensional relief art: Hang on side walls Three-dimensional relief art: Hang on side walls Experiment with ensemble set-up to potentially shield the director from excessive noise. Experiment with ensemble set-up to potentially shield the director from excessive noise.

68 Rehearsal Room Design According to Wenger: According to Wenger: Rehearsal rooms should be a minimum of 2500 square feet. This should accommodate an ensemble of 60-70 members. Rehearsal rooms should be a minimum of 2500 square feet. This should accommodate an ensemble of 60-70 members. Ceilings should rise to 18-22 feet. Ceilings should rise to 18-22 feet. What are the dimensions of your rehearsal space?

69 What about our students? Talk to our students about noise- induced hearing loss and their risks. Talk to our students about noise- induced hearing loss and their risks. Encourage (if not require) our students to wear earplugs in certain rehearsals (drumline rehearsals in particular) Encourage (if not require) our students to wear earplugs in certain rehearsals (drumline rehearsals in particular) Encourage our students to reduce the amount of noise in their home environments (iPod usage especially!!) Encourage our students to reduce the amount of noise in their home environments (iPod usage especially!!)

70 Suggestions for Future Research 1. Determine the role of rehearsal room design and dimensions in the prevention of excessive noise exposure. 2. Experiment with ensemble seating arrangements in order to reduce noise exposure in both the conductor and the individual musicians.


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