Noise Evaluation of 

Elementary and High 

School Music Classes 

and Indoor Marching 

Band Rehearsals – 

Alabama

Lilia Chen, MS, CIH

Scott E. Brueck, MS, CIH

Health Hazard Evaluation Report

HETA 2011-0129-3160

May 2012

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

Workplace

Safety and Health

 National Institute for Occupational 

Safety and Health
The employer shall post a copy of this report 

for a period of 30 calendar days at or near 

the workplace(s) of affected employees. The 

employer shall take steps to insure that the 

posted determinations are not altered, defaced, 

or covered by other material during such 

period. [37 FR 23640, November 7, 1972, as 

amended at 45 FR 2653, January 14, 1980].
Health Hazard Evaluation Report 2011-0129-3160 Page i

Report Abbreviations................................................................................................ii

Highlights of the NIOSH Health Hazard Evaluation........................iii

Summary .........................................................................................................v

Introduction ...................................................................................................1

Assessment.....................................................................................................1

Results and Discussion...............................................................................2

Conclusions................................................................................................. 12

Recommendations.................................................................................... 12

References.................................................................................................... 14

Contents

Acknowledgments Acknowledgments and Availability of Report................................ 20

Appendix A Occupational Exposure Limits and Health Effects......................... 16

Appendix B Methods........................................................................................................ 19
Page ii Health Hazard Evaluation Report 2011-0129-3160

Abbreviations

AL Action level

CFR Code of Federal Regulations

dB Decibel

dBA Decibel, A-scale

HHE Health hazard evaluation

Hz Hertz

KHz Kilohertz

NAICS North American Industry Classification System

NIHL Noise-induced hearing loss

NIOSH National Institute for Occupational Safety and Health

OSHA Occupational Safety and Health Administration

PEL Permissible exposure limit

REL Recommended exposure limit

SLM Sound level meter

STS Standard threshold shift

TWA Time-weighted average 
Health Hazard Evaluation Report 2011-0129-3160 Page iii

The National Institute for 

Occupational Safety and 

Health (NIOSH) received 

an employee request 

for a health hazard 

evaluation (HHE) at a high 

school in Alabama. The 

employee submitted the 

HHE request because 

of concerns about 

hearing loss from loud 

noise exposures during 

music classes and band 

rehearsals.

Highlights of the

NIOSH Health

Hazard Evaluation

What NIOSH Did

● We evaluated the band director’s noise exposures on 

November 1–2, 2011.

● We measured noise levels at different frequencies during 

marching band rehearsals.

● We calculated reverberation times for the band room and 

cafeteria. Reverberation time is the time it takes for a sound 

to go down 60 decibels from its original intensity.

What NIOSH Found

● The band director’s full-shift noise exposure reached and 

exceeded occupational exposure limits.

● The highest noise exposure reached 110 decibels, A-scale. 

This level occurred in the band room during marching band 

rehearsal.

● The highest noise levels occurred at 125 hertz during 

marching band rehearsals. 

● The noise levels were greater in the band room than in the 

cafeteria.

● Room reverberation times of the band room and cafeteria 

were within recommended ranges. These ranges have been 

recommended by other researchers.

● The band room was not a large enough rehearsal space for 

the number of students in the high school marching band.

What Managers Can Do

● Provide a practice space acoustically designed for musical 

performance. The space should also be sized appropriately 

for the number of students. Until such a space is available, 

continue to allow marching band rehearsals to occur in larger 

spaces that contain sound absorbent materials.

● Increase the distance between students playing musical 

instruments and the music instructor. This can be done by 

changing the set-up of the band room.

● Develop a hearing conservation program that includes 

annual audiometric testing and training. The band director 

and other music teachers should be enrolled in this program.
Page iv Health Hazard Evaluation Report 2011-0129-3160

Highlights of the

NIOSH Health

Hazard Evaluation

 (continued)

 

● Provide the band director with flat attenuation hearing 

protection, also known as musician ear plugs. These ear plugs 

should be used until an acoustically appropriate space is available 

for marching band rehearsals and noise monitoring results are 

documented at levels below occupational exposure limits.

● Teach music students, especially those involved in marching 

band, and their parents about noise-induced hearing loss. 

Include information on the symptoms of the condition and 

how to prevent hearing loss.

What Employees Can Do

● Wear musician ear plugs during marching band rehearsal. 

These ear plugs can also be worn during other music classes 

that are loud.

● Increase the distance between the band director and students 

playing instruments whenever possible.

● Hold marching band rehearsals outdoors when possible. 

When rehearsing indoors, use a larger space that contains 

absorbent materials to reduce noise levels until an 

appropriately designed space becomes available.

● Ask the marching band students to play softly when 

rehearsing in the band room.
Health Hazard Evaluation Report 2011-0129-3160 Page v

The band director’s fullshift noise exposure 

exceeded the NIOSH REL, 

reached the OSHA AL, 

but did not exceed the 

OSHA PEL. Marching band 

rehearsal produced the 

highest noise exposures. 

The band director should 

wear musician earplugs 

until an area acoustically 

designed for musical 

performance is available. 

Administrators should 

educate music teachers, 

music students, and their 

parents on symptoms and 

ways to prevent NIHL.

Summary

On July 1, 2011, NIOSH received an HHE request from an 

employee at a high school in Alabama concerned about noise 

exposures, especially during marching band rehearsal. On 

November 1–2, 2011, NIOSH investigators evaluated the band 

director’s exposures to noise during a typical work day in the band 

room and during marching band rehearsal in the cafeteria.

We took personal noise exposure measurements on the band 

director during marching band rehearsal in the cafeteria on 

November 1, 2011 and during the entire school day on November 

2, 2011. We also took area noise measurements and performed 

octave band frequency spectrum analyses. We measured the 

dimensions of the band room and cafeteria and calculated 

reverberation times for these areas.

The band director’s full-shift TWA noise exposure reached the 

OSHA AL and exceeded the NIOSH REL of 85 dBA. It did not 

exceed the OSHA PEL. Marching band rehearsal produced the 

highest noise exposures, reaching 110 dBA. The TWA for marching 

band rehearsal in the band room was 2 dBA higher than rehearsal in 

the cafeteria. Octave band analysis during marching band rehearsal 

showed that the highest noise levels of 99 dB occurred at 125 Hz 

and were greater in the band room compared to the cafeteria. Room 

reverberation times ranged from 0.5 to 0.8 seconds in the band 

room and 0.7 to 1.0 seconds in the cafeteria. These reverberation 

times fell within ranges recommended in other studies.

Because of the high noise levels produced during marching band 

rehearsals, an area acoustically designed for musical performance 

should be used. Until such a space is available, marching band 

rehearsals should occur outside when possible or in larger indoor 

spaces, preferably areas that contain sound absorbent materials. 

The band director should use flat attenuation hearing protection 

(musician earplugs). Because noise exposures reached the OSHA 

AL and exceeded the NIOSH REL, a hearing conservation program 

is necessary. The band director and future music teachers should 

have yearly audiometric evaluations in accordance with the OSHA 

standard and NIOSH recommendations. Teachers, students, and 

their parents who are involved with music, especially marching band, 

should be educated on NIHL symptoms and prevention.

Keywords: NAICS 611110 (Elementary and Secondary Schools), 

noise, sound, music, band, band director, music teacher, hearing 

loss, NIHL, reverberation time 
Page 1 Health Hazard Evaluation Report 2011-0129-3160

Introduction

On July 1, 2011, NIOSH received a request from an employee at a high 

school in Alabama to assess noise exposures, especially during high 

school marching band rehearsal. On November 1–2, 2011, NIOSH 

investigators evaluated the band director’s noise exposures during a 

typical work day.

The band director taught all the music classes and rehearsals at this 

high school. The school day was split into 10 periods ranging from 30 

minutes to 50 minutes. Music classes consisted of teaching fifth and 

sixth grade band and music arts and directing marching band rehearsal. 

Most classes consisted of approximately 15 to 30 students. However, 

marching band rehearsal consisted of approximately 90 students. It 

lasted about 50 minutes each day, and was reported to be the loudest 

class of the day. The marching band included woodwind, brass, and 

percussion instruments such as flutes, clarinets, trumpets, trombones, 

tubas, and drums. All classes took place in the band room, which was 

approximately 1,700 square feet. Marching band rehearsal took place in 

the band room until September 2011, when rehearsal was moved to the 

cafeteria because of its larger size (approximately 6,000 square feet).

In addition to regularly scheduled activities, the band director provided 

lessons after school prior to sectional and state auditions. These sessions 

contributed to his overall noise exposure.

Assessment

We held an opening meeting on November 1, 2011, with employer 

and employee representatives. On November 1–2, 2011, we 

interviewed the band director, observed classroom activities 

and marching band rehearsal, and measured noise. The band 

director wore a personal integrating noise dosimeter during 

marching band rehearsal in the cafeteria on November 1, 2011 

and during his entire work shift on November 2, 2011. We also 

used two additional noise dosimeters to take full-shift area noise 

measurements on each side of the band room. We performed 

octave band frequency spectrum analysis (measurement of 

noise levels in different frequencies) in the cafeteria and in the 

band room using two integrating SLMs equipped with real-time 

frequency spectrum analyzers. The SLMs were mounted on tripods 

at a height of approximately 5 feet to represent the ear position of 

the standing band director. For octave band measurements in each 

room, we positioned one SLM at the back of the room near the 

percussion section and the second SLM at the front of the room 

near the band director. We also measured the dimensions of the 

band room and cafeteria and calculated reverberation times for 
Health Hazard Evaluation Report 2011-0129-3160 Page 2

each room. More information on occupational exposure limits 

and health effects for noise can be found in Appendix A. More 

information on sampling methodology for noise can be found in 

Appendix B.

Assessment

 (continued)

Results and

Discussion The results of TWA noise exposure measurements during music 

classes and marching band rehearsal in the band room are listed 

in Table 1. The band director’s full-shift TWA noise exposure in 

the band room did not exceed the OSHA PEL of 90 dBA, but 

reached the OSHA AL of 85 dBA and exceeded the NIOSH REL 

of 85 dBA, reaching a TWA of 90 dBA. Because the band director 

was the only employee who taught music classes and rehearsals, 

we took two additional area measurements with noise dosimeters. 

One dosimeter was placed on each side of the room near the 

storage racks. Neither area dosimeter noise measurement exceeded 

the OSHA AL or PEL. The area dosimeters were placed several 

feet further from the group of students (source of noise) compared 

to the distance the band director stood from the students. These 

results show that increasing the distance from the students 

decreased noise exposure. The noise measurements for the area 

dosimeter on the left side of the room were 3 dBA higher than on 

the right side; measurements on the left side showed TWA noise 

levels above the NIOSH REL. Most likely, this difference occurred 

because the area dosimeter on the left was a few feet closer to the 

students than the dosimeter on the right. Additionally, most of 

the larger percussion instruments were located on the left side of 

the room; the brass instruments on the right side of the room were 

directed toward the band director and away from the dosimeter 

when students were playing the instruments.

Table 1. Dosimeter noise exposure results from employee and area measurements in the band room*

Description Duration OSHA AL OSHA PEL NIOSH REL

(hours:minutes)

TWA†

Projected 

8-hour 

TWA‡

TWA†

Projected 

8-hour 

TWA‡

TWA†

Projected 

8-hour 

TWA‡

(dBA) (dBA) (dBA) (dBA) (dBA) (dBA)

Band director – personal 7:01 86 85 84 83 90 90

Band room area – left 6:42 80 79 78 77 87 87

Band room area – right 6:43 77 76 75 74 85 84

Occupational exposure limits 85 90 85

*Exposures at or exceeding noise exposure limits are in bold and italicized font.

†TWA noise exposures for the duration of the noise monitoring period

‡Projected 8-hour TWA noise exposures assume noise levels outside sampling period were below 80 dBA.
Page 3 Health Hazard Evaluation Report 2011-0129-3160

Results and

Discussion

 (continued)

The band director’s noise exposure time history profile during 

personal noise dosimeter measurements in the band room is shown 

in Figure 1. During fifth grade and sixth grade music and band 

classes and discovery rehearsal (an elementary music class), noise 

levels mostly ranged from 80 to 100 dBA and exceeded 100 dBA 

in a few instances. However, during high school marching band 

rehearsal, noise levels increased to 90 to 100 dBA and exceeded 

100 dBA numerous times. Noise levels between music classes were 

below 85 dBA most of the time. Figure 2 shows the noise exposure 

time history profile for the 50 minutes of high school marching 

band practice in the band room.

Fifth grade 

band & sixth 

grade music

Sixth grade 

band

Discovery 

rehearsal

High school 

marching band 

rehearsal

Figure 1. Noise exposure time history profile for the band director in the band room.

Table 2 compares the band director’s TWA noise exposures during 

the loudest music classes on the basis of personal dosimeter results. 

Noise exposure during marching band rehearsal in the band room 

and in the cafeteria was substantially higher than during other music 

or band classes. Exposure during marching band rehearsal exceeded 

90 dBA using NIOSH and OSHA measurement criteria and was 

the primary contributor to the band director’s full-shift TWA noise 

exposure. If the average noise level during marching band rehearsal 

was reduced by 3 dBA, the band director’s TWA exposure would 

have been less than 85 dBA on the basis of OSHA criteria.
Health Hazard Evaluation Report 2011-0129-3160 Page 4

Results and

Discussion

 (continued)

Noise exposure during marching band rehearsal was 2 dBA higher 

in the band room compared to the cafeteria. The most likely reason 

for this difference is that the cafeteria was a much larger space with 

reflective surfaces located farther away from the band and band director.

Figure 2. Noise exposure time history profile for the band director during high school marching band rehearsal in 

the band room.

Table 2. Band director’s personal noise exposure measurement results during various music classes*

Description Duration

(hour:minutes) 

OSHA AL

TWA

(dBA)

OSHA PEL

TWA

(dBA)

NIOSH REL

TWA

(dBA)

Marching band rehearsal in cafeteria 0:42 94 93 95

Marching band rehearsal in band room 0:51 96 95 97

Fifth grade band class 0:25 88 84 90

Sixth grade elementary music class 0:30 89 87 91

Sixth grade band class 0:30 91 89 92

Discovery rehearsal class 0:50 89 86 91

*TWA noise exposures for the duration of the monitoring period

The noise exposures measured in this evaluation were within the 

range reported in a previous study in which the 8-hour TWA noise 

exposures of 18 music teachers from 15 schools were found to 

range from 79 to 93 dBA [Behar et al. 2004]. In that study, band 

activities had the loudest continuous noise levels compared to 

singing, percussion, keyboard, or recorder activities. Band activities 

performed in the same classroom ranged from 86 to 98 dBA 
Page 5 Health Hazard Evaluation Report 2011-0129-3160

depending on the number of students in the class and whether they 

were learning, performing, or listening to examples shown by the 

teacher [Behar et al. 2004]. Another study of the noise exposures 

of high school band directors during rehearsals of jazz, percussion, 

or concert band ensembles reported TWA exposures that ranged 

from 85 to 93 dBA [Owens 2004]. The number of students ranged 

from 8 to 24 in the jazz ensembles and from 30 to 75 in the concert 

band. Maximum noise levels ranged from 101 to 115 dBA, which 

is similar to the maximum levels we measured. A research study of 

university music students found that brass instrument players had 

significantly higher mean average noise exposure levels (95.2 dBA) 

compared to woodwind players (90.4 dBA), percussion players (90.1 

dBA), vocalists (88.4 dBA), or string players (87.0 dBA) [Phillips and 

Mace 2008]. This indicates that the proximity of the band director 

(and students) to specific groups of instruments can affect noise 

exposure levels. Our noise measurements only provided the noise 

exposure of the band director. Students are likely to have lower 

8-hour TWA noise exposures because they spend less time in music 

classes and rehearsals at school. However, at a noise exposure level 

of 94 dBA the NIOSH REL is exceeded after 1 hour of exposure, 

and at a noise exposure level of 97 dBA the REL is exceeded after 

30 minutes.

A study of audiometric test results from 104 music educators 

participating in summer music workshops found evidence 

that being a high school band director carried a slight risk for 

NIHL [Cutietta et al. 1994]. However, less than 20% of the high 

school band directors had NIHL, and the degree of loss was 

highly variable. Studies have also looked at potential hearing 

loss of student musicians. In one study, students had a high risk 

of excessive noise exposure from social and study-based music 

activities [Barlow 2010]. In another study, the prevalence of NIHL 

in 329 student musicians aged 18 to 25 years was 45% compared 

to 11.5% in the general population [Phillips et al. 2010]. Although 

these studies surveyed undergraduate student musicians, many 

high school student musicians pursue musical study in college, 

attend loud concerts or nightclubs, and listen to loud music on 

personal music listening devices or stereos. Music teachers may 

also be exposed to loud noise outside of the classroom from 

playing music, listening to music, or other hobbies. Therefore, it 

is important to educate teachers and students about the risk of 

hearing loss from excessive noise exposures and inform them about 

ways to protect and preserve hearing.

Results and

Discussion

 (continued)
Health Hazard Evaluation Report 2011-0129-3160 Page 6

Results and

Discussion

 (continued)

Octave Band Analysis

Octave band noise measurements provide information about 

the frequency distribution of noise. Because the energy from 

noise is usually widely distributed over many frequencies, the 

frequency range is broken into a smaller range of frequencies 

(called bandwidths), the most common being the octave band 

(defined as a frequency band where the upper band frequency 

is twice the lower band frequency). Octave band analysis allows 

for determination of the dominant noise frequencies and can 

be useful for identifying potential noise controls. For example, 

if low frequency noise is dominant (i.e., the highest octave band 

noise levels occur in frequencies of 500 Hz or less), noise is 

likely generated by vibration, and noise controls should focus on 

reducing or isolating the source of vibration. If high frequency 

noise is dominant (i.e., the highest octave band noise levels occur 

in frequencies of 2,000 Hz or greater), noise enclosures, barriers, or 

sound absorption systems are typically the most effective approach 

[Driscoll and Royster 2003].

One-third octave band noise frequency measurements were collected 

when students in marching band rehearsed in the cafeteria and the 

band room. The results are shown in Figure 3. Our measurements 

showed that the highest noise levels (99 dB) occurred in the band 

room at a frequency of 125 Hz and were greater than 90 dB across 

all the one-third octave bands; levels ranged from 100 Hz to 800 Hz 

in the band room and from 125 Hz to 200 Hz in the cafeteria. The 

highest noise level reached in the cafeteria was 96 dB (at 125 Hz). 

The dominant noise levels in the low frequencies were mostly from 

noise generated by percussion instruments.

Noise levels in the band room were also consistently higher than 

in the cafeteria for one-third octave band frequencies 125 Hz to 

20,000 Hz. Interestingly, noise levels were higher in the cafeteria 

than in the band room across the frequencies from 12.5 Hz to 80 

Hz. These differences are most likely because of the small size of 

the band room and the shorter wavelength of the higher frequency 

noise, which resulted in relatively more noise reverberation and 

higher noise levels for those frequencies in the band room. The 

large size of the cafeteria and the longer wavelength of very low 

frequency noise resulted in relatively more reverberation and 

higher noise levels for the low frequencies in the cafeteria.
Page 7 Health Hazard Evaluation Report 2011-0129-3160

Figure 3. One-third octave band noise levels taken during marching band rehearsal in the band room 

and cafeteria over approximately 30 minutes.

Room Reverberation Time

Reverberation time is the time in seconds required for a steadystate sound to reach one millionth or a reduction of 60 dB 

of its original intensity after the sound source has stopped. 

Reverberation time is important because it indicates sound quality 

within a space for speech and music. It is based on the volume of 

the room, the surface area, and the sound absorbent coefficient of 

the materials covering the surface areas of the room.

Materials have varying abilities to absorb sound energy, also known 

as the sound absorbent coefficient. Materials do not absorb sound 

equally at all frequencies because of the wavelength differences 

between high and low frequencies. Most common building 

materials have been tested at a wide range of frequencies to 

determine their ability to absorb sound energy (Table 3).

We calculated reverberation time in the band room and the 

cafeteria (Table 4). For both areas, we did not take into account 

absorption by the occupants or furnishings, so our results indicate 

a worst-case scenario. The band room walls were constructed 

Results and

Discussion

 (continued)
Health Hazard Evaluation Report 2011-0129-3160 Page 8

of painted concrete blocks. However, most of the back wall was 

covered with wooden storage shelves filled with instruments and 

with trophies on top. The side and front walls had some wooden 

shelves, wood or wood composite storage cabinets, metal filing 

cabinets, banners, and trophies. None of these materials had 

been tested for sound absorption coefficients. Therefore, we did 

two calculations, one using the painted concrete block’s sound 

absorption coefficient and the other using the plywood paneling’s 

sound absorption coefficient. This gave us a range of reverberation 

times to account for the untested materials along the walls.

Table 3. Sound absorption coefficients for common building materials* 

Frequency (Hz)

125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz NRC†

Wall surface material:

Concrete block (painted) 0.1 0.05 0.06 0.07 0.09 0.08 0.07

Plywood panel, 3/8 inch thick 0.28 0.22 0.17 0.09 0.1 0.11 0.15

Fabrics:

Light velour, 10 oz/sq. yard‡ 

hung in contact with wall 0.03 0.04 0.11 0.17 0.24 0.35 0.14

Medium velour, 14 oz/sq.yard 

draped to half area 0.07 0.31 0.49 0.75 0.7 0.6 0.56

Heavy velour, 18 oz/sq.yard 

draped to half area 0.14 0.35 0.55 0.72 0.7 0.65 0.58

Glass – Ordinary window glass 0.35 0.25 0.18 0.12 0.07 0.04 0.16

Sprayed-on acoustic material 

– 1” cellulose applied to metal 

lath, 2.5 pounds per cubic foot

0.47 0.9 1.1 1.03 1.05 1.03 1.02

Floor surface material:

Vinyl tile or linoleum on 

concrete 0.02 0.03 0.03 0.03 0.03 0.02 0.03

Carpet, heavy on concrete 0.02 0.06 0.14 0.37 0.6 0.65 0.29

Carpet, heavy, on 40-ounce hair 

felt or foam rubber 0.08 0.24 0.57 0.69 0.71 0.73 0.55

Wood 0.15 0.11 0.1 0.07 0.06 0.07 0.06

Ceiling surface material:

Acoustic tile – suspended§ 0.5 0.7 0.6 0.7 0.7 0.5 0.64

Other:

Opening, stage depending on furnishings 0.25 to 0.75

*Source: Berger et al. 2003, Table 9.10

†NRC – noise reduction coefficient; average of coefficients between 250 Hz and 2000 Hz.

‡oz/sq. yard – ounce per square yard

§Source: Hall 2002, Table 15.1

Results and

Discussion

 (continued)
Page 9 Health Hazard Evaluation Report 2011-0129-3160

During our evaluation, the food service area of the cafeteria was 

caged off so we could not take dimensional measurements. For our 

calculations of this area, we used the sound absorption coefficient 

of “openings: stage depending on furnishings.” Our reverberation 

time estimates were based on calculated values; these results could 

differ from values obtained using equipment specifically designed 

to measure reverberation.

Table 4. Calculated reverberation time estimates (seconds) for the band room and cafeteria at various sound 

frequencies

Room 

Volume 

Frequency (Hz)

(cubic feet) 125 250 500 1000 2000 4000 NRC*

Band room† 17,500 0.6 0.5 0.6 0.6 0.6 0.8 0.6

Band room‡ 0.8 0.7 0.7 0.6 0.6 0.8 0.7

Cafeteria§ 63,000 0.9 0.7 0.8 0.7 0.7 1.0 0.8

*NRC – noise reduction coefficient; average of coefficients between 250 Hz and 2000 Hz

†Calculated with plywood paneling sound absorption coefficient

‡Calculated with painted concrete block sound absorption coefficient

§Best estimate of room volume because separation of the service area prevented the dimensional measurement 

of the food service area

Recommended reverberation times for music rooms and halls 

depend on the type of music being performed and the size of the 

room. Recommended ranges are based on multiple tests in a variety 

of environments and on determining the reactions of different 

people at measured reverberation rates. Large rooms where music 

will be played, such as concert halls, are designed to have longer 

reverberation times (1.2 to 2.3 seconds) [Beranek 2006]. For rooms 

designed for music education where clear recognition of speech 

and changes in instrument nuances need to be heard, a shorter 

reverberation time is preferred [Hunecke 2011].

Examples of recommended reverberation rates are shown in 

Figure 4 [Hemond 1983] and Figure 5 [Hall 2002]. A series of 

case studies led researchers to recommend that band rooms have 

reverberation times of 0.6 to 0.8 seconds and a ceiling height 

of 16 to 24 feet [Paek et al. 2003]. Hemond recommended 

music room reverberation times of 1.0 to 1.2 seconds, whereas 

a classroom should have a 0.7-second reverberation time so 

speech can be heard clearly [Hemond 1983]. Sheaffer determined 

room reverberation times using a model and calculated that 

music practice rooms require 0.3 to 1 second of reverberation 

time depending on room volume [Sheaffer 2007]. Estimated 

Results and

Discussion

 (continued)
Health Hazard Evaluation Report 2011-0129-3160 Page 10

reverberation times ranged from 0.5 to 0.8 seconds for the band 

room and from 0.7 to 1.0 second in the cafeteria we evaluated; 

these times are within the recommended ranges.

Results and

Discussion

 (continued)

Figure 4. Recommended reverberation times [Hemond 1983].

Figure 5. Recommended reverberation times [Hall 2002].
Page 11 Health Hazard Evaluation Report 2011-0129-3160

In a study at a music institute in Finland, researchers measured 

reverberation times before and after installing sound absorbent 

materials in six classrooms and a music hall and administered a 

questionnaire to music teachers before and after the installation. 

The authors concluded that reducing the room reverberation times 

did not significantly decrease the teachers’ noise exposure levels; 

however, teachers perceived the quality of sound to have improved 

and reported higher job satisfaction [Toppila and Olkinuora 2010].

Installing sound absorbent materials in the band room might 

reduce reverberation time, but this alone may not significantly 

reduce the band director’s noise exposure because of the relatively 

small size of the band room, the large number of students in the 

space, and the band director’s proximity to the students during 

rehearsal. It may be possible to reduce the band director’s noise 

exposure in the band room through a combination of approaches 

including increasing the distance of the band director from the 

students during rehearsal, installing sound absorbent material on 

the wall in the front of the classroom, and instructing students 

to play more quietly during rehearsal in the band room. Because 

the band room was designed as a classroom and not for musical 

performance purposes, and because it was not designed for 

the large number of band students in the room for rehearsals, 

these noise reduction approaches would likely be more effective 

in a properly sized practice space. Adequate room volume is 

necessary to allow sound energy to dissipate, and higher ceiling 

heights reduce the loudness of high energy brass and percussion 

instruments [Paek et al. 2003]. Additionally, the room size should 

be appropriate for the number of students practicing or performing 

in the space. It has been observed that some music instructors 

teach in rooms designed too small for the numbers of students 

actually present [Paek et al. 2003]. A guideline is that a high school 

band room for 60 to 75 musicians should have a floor space of 

2,500 ft2

 and a ceiling height of 18 to 22 ft. [Wenger 2001].

Results and

Discussion

 (continued)
Health Hazard Evaluation Report 2011-0129-3160 Page 12

Conclusions

Personal noise measurements taken during the band director’s 

work day did not exceed the OSHA PEL but reached the OSHA 

AL of 85 dBA and exceeded the NIOSH REL, reaching a TWA 

of 90 dBA. His short-term exposure during high school marching 

band rehearsals exceeded 90 dBA. Noise exposures were highest 

during marching band rehearsal in the band room, but noise 

exposure levels during rehearsal in the cafeteria were also high. 

Calculated reverberation times in the band room were appropriate 

for teaching music classes, but the band room was not designed for 

use as a music rehearsal or performance space and was too small 

for the number of students in the marching band. Marching band 

rehearsal should take place outside, when possible, or in an area 

appropriately sized for the number of students and acoustically 

designed for musical rehearsals or performances. Until an 

acoustically designed and properly sized space can be constructed, 

marching band rehearsals should take place in alternative rehearsal 

spaces such as a larger room with sound absorbent materials or 

in the cafeteria. Because of the high noise levels during marching 

band rehearsal, a hearing conservation program is needed for the 

band director, including hearing protection, yearly audiometric 

evaluations, and training on noise exposures. Music students and 

their parents should also be educated on the potential hazards of 

loud music and ways to protect their hearing.

Recommendations

On the basis of our findings, we recommend the actions listed 

below to create a more healthful workplace. Our recommendations 

are based on the hierarchy of controls approach (refer to Appendix 

A: Occupational Exposure Limits and Health Effects). This 

approach groups actions by their likely effectiveness in reducing 

or removing hazards. In most cases, the preferred approach is to 

eliminate the hazard or processes and install engineering controls 

to reduce exposure or shield employees. Until such controls are 

in place, or if they are not effective or feasible, administrative 

measures and/or personal protective equipment may be needed. 

Personal protective equipment is the least effective means for 

controlling employee exposures. Proper use of personal protective 

equipment requires a comprehensive program, and calls for a high 

level of employee involvement and commitment to be effective.

1. Hold marching band rehearsal outside or in a room 

appropriately sized for the number of band students 

and acoustically designed for musical rehearsals and 
Page 13 Health Hazard Evaluation Report 2011-0129-3160

Recommendations

 (continued) performances. Until an acoustically designed space can be 

constructed, marching band rehearsals should take place in 

alternative rehearsal spaces such as the cafeteria or a larger 

room with sound absorbent materials. If marching band 

rehearsal must take place in the band room, all students 

should be asked to play softly and focus on technique, and 

practice louder dynamics when rehearsals take place outside 

or in the larger rehearsal areas.

2. Stand away from high sound reflective surfaces, such as 

blackboards, when leading music classes and marching band 

rehearsal. If this is not possible, then cover such surfaces 

with sound absorbent material.

3. Move the students slightly farther back in the classroom to 

create more distance from the band director.

4. Provide the band director with flat attenuation “musician” 

ear plugs until an acoustically appropriate space is available 

and noise monitoring results are documented to be below 

occupational exposure limits. These hearing protectors 

attenuate sound levels evenly across frequencies to maintain 

sound quality. Administrators should provide training for 

the proper fit, use, and care of the ear plugs.

5. Establish a hearing conservation program to include the 

band director and future music teachers in accordance 

with the OSHA hearing conservation standard [29 CFR 

1910.95] and NIOSH recommendations. This program 

should provide guidelines for reducing the risk of hearing 

loss, include annual audiometric testing and follow-up, and 

include training on using hearing protectors. Audiometric 

testing allows for the early detection of hearing loss and 

provides opportunities for interventions. More information 

on establishing a hearing conservation program can be 

found at http://www.osha.gov/dts/osta/otm/noise/

hcp/index.html and http://www.osha.gov/Publications/

osha3074.pdf.

6. Share information on the symptoms and prevention of 

NIHL with band students and their parents.
Health Hazard Evaluation Report 2011-0129-3160 Page 14

References

Barlow C [2010]. Potential hazard of hearing damage to students 

in undergraduate popular music courses. Med Probl Perform Art 

25(4):175–182.

Behar A, MacDonald E, Lee J, Cui J, Kunov H, Wong W [2004]. 

Noise exposure of music teachers. J Occ Env Hyg 1(4):243–247.

Beranek LL [2006]. Analysis of Sabine and Eyring equations and 

their application to concert hall audience and chair absorption. 

Acou Soc of Am 120(3):1399–1410.

Berger EH, Royster LH, Royster JD, Driscoll DP, Layne M, eds. 

[2003]. The noise manual. 5th rev. ed. Fairfax, VA: American 

Industrial Hygiene Association.

CFR. Code of Federal Regulations. Washington, D.C.: U.S. 

Government Printing Office, Office of the Federal Register.

Cutietta RA, Klich RJ, Royse D, Rainbolt H [1994]. The incidence 

of noise-induced hearing loss among music teachers. J Res Music 

Ed 42(4):318–330.

Driscoll DP, Royster LH [2003]. Noise control engineering. In: 

Berger EH, Royster LH, Royster JD, Driscoll DP, Layne M. eds, 

The noise manual, 5th ed. Fairfax, VA: American Industrial 

Hygiene Association, pp. 279–378; [Reference: Table 9.5, pp. 

298–300].

Hall DE [2002]. Musical acoustics, 3rd ed. Pacific Grove, CA: 

Brooks/Cole Publishing, pp. 324–336.

Hemond CJ [1983]. Engineering acoustics and noise control. 

Englewood Cliffs, NJ: Prentice-Hall, pp. 53–57.

Hunecke J [2011]. Reverberation time. [http://www.hunecke.de/

en/knowledge/room-acoustics/reverberation-time.html]. Date 

accessed: April 2012.

Owens DT [2004]. Sound pressure levels experienced by the high 

school band director. Med Prob Perf Artists 19(3):109–115.

Paek H, Siebein GW, Kim B [2003]. Case studies of acoustical 

design of rooms for music instructions in schools. Cleveland, OH: 

Noise-Con.
Page 15 Health Hazard Evaluation Report 2011-0129-3160

References

 (continued) Phillips SL, Mace S [2008]. Sound level measurements in music 

practice rooms. Mus Per Research 2:36–47.

Phillips SL, Henrich VC, Mace ST [2010]. Prevalence of noiseinduced hearing loss in student muscians. Int J Aud 49(4):309–

316.

Sheaffer J [2007]. Prediction of reverberation times. Prediction 

and evaluation of RT design criteria. [http://www.acdg.co.il/pdf/

RT_Criteria.pdf]. Date accessed: April 2012.

Toppila E, Olkinuora P [2010]. Facilities for music education and 

their acoustical design. Int J Occ Saf Erg 16(1):93–104.

Wenger Corporation [2001]. Planning guide for secondary school 

music facilities. Owatonna, MN: Wenger Corporation.
Health Hazard Evaluation Report 2011-0129-3160 Page 16

Appendix A: Occupational Exposure Limits and ealth Effects

NIHL is an irreversible condition that progresses with noise exposure. It is caused by damage to the nerve 

cells of the inner ear and, unlike some other types of hearing disorders, cannot be treated medically 

[Berger et al. 2003]. More than 22 million U.S. workers are estimated to be exposed to workplace noise 

levels above 85 dBA [Tak et al. 2009]. NIOSH estimates that workers exposed to an average daily noise 

level of 85 dBA over a 40-year working lifetime have an 8% excess risk of material hearing impairment. 

This excess risk increases to 25% for an average daily noise exposure of 90 dBA [NIOSH 1998]. NIOSH 

defines material hearing impairment as an average of the hearing threshold levels for both ears that 

exceeds 25 dB at frequencies of 1,000, 2,000, 3,000, and 4,000 Hz.

Although hearing ability commonly declines with age, exposure to excessive noise can increase the rate 

of hearing loss. In most cases, NIHL develops slowly from repeated exposure to noise over time, but 

the progression of hearing loss is typically the greatest during the first several years of noise exposure. 

NIHL can also result from short duration exposures to high noise levels or even from a single exposure 

to an impulse noise or a continuous noise, depending on the intensity of the noise and the individual’s 

susceptibility to NIHL [Berger et al. 2003]. Noise-exposed workers can develop substantial NIHL before 

it is clearly recognized. Even mild hearing losses can impair one’s ability to understand speech and hear 

many important sounds. In addition, some people with NIHL also develop tinnitus, a condition in 

which a person perceives hearing sound in one or both ears, but no external sound is present. Persons 

with tinnitus often describe hearing ringing, hissing, buzzing, whistling, clicking, or chirping like crickets. 

Tinnitus can be intermittent or continuous, and the perceived volume can range from soft to loud. 

Currently, no cure for tinnitus exists.

The preferred unit for reporting of noise measurements is the decibel, A-weighted (dBA). A-weighting is 

used because it approximates the “equal loudness perception characteristics of human hearing for pure 

tones relative to a reference of 40 dB at a frequency of 1,000 Hz” and is considered to provide a better 

estimation of hearing loss risk than using unweighted or other weighting measurements [Earshen 2003]. 

The dB unit is dimensionless, and it represents the logarithmic ratio of the measured sound pressure level 

to an arbitrary reference sound pressure (20 micropascals, which is defined as the threshold of normal 

human hearing at a frequency of 1,000 Hz). Decibels are used because of the very large range of sound 

pressure levels audible to the human ear. Because the dB is logarithmic, an increase of 3 dB is a doubling 

of the sound energy, an increase of 10 dB is a tenfold increase, and an increase of 20 dB is a hundredfold 

increase in sound energy. Noise exposures expressed in decibels cannot be averaged by taking the 

arithmetic mean.

Workers exposed to noise should have baseline and yearly hearing tests to evaluate their hearing thresholds 

and determine whether their hearing has changed over time. Hearing testing should be done in a quiet 

location, such as an audiometric test booth where background noise does not interfere with accurate 

measurement of hearing thresholds. In workplace hearing conservation programs, hearing thresholds must 

be measured at 500, 1,000, 2,000, 3,000, 4,000, and 6,000 Hz. Additionally, NIOSH recommends that 

8,000 Hz should also be tested [NIOSH 1998]. For workers covered by the OSHA hearing conservation 

standard, changes from baseline hearing thresholds must be analyzed to determine if the change is 

substantial enough to meet OSHA criteria for an STS. OSHA defines an STS as a change in hearing 
Page 17 Health Hazard Evaluation Report 2011-0129-3160

Appendix A: Occupational Exposure Limits and ealth Effects

(continued)

threshold relative to the baseline hearing test of an average of 10 dB or more at 2,000, 3,000, and 4,000 

Hz in either ear [29 CFR 1910.95]. If an STS occurs, the company must determine if the hearing loss also 

meets the requirements to be recorded on the OSHA 300 Log of Injury and Illness [29 CFR 1904.1]. In 

contrast to OSHA, NIOSH defines a significant threshold shift as an increase in the hearing threshold 

level of 15 dB or more, relative to the baseline audiogram, at any test frequency in either ear measured 

twice in succession [NIOSH 1998].

Hearing test results are often presented in an audiogram, which is a plot of an individual’s hearing 

thresholds (y-axis) at each test frequency (x-axis). Hearing threshold levels are plotted such that fainter 

sounds are shown at the top of the y-axis, and more intense sounds are plotted below. Typical audiograms 

show hearing threshold levels from –10 or 0 dB to about 100 dB. Lower frequencies are plotted on the 

left side of the audiogram, and higher frequencies are plotted on the right. NIHL often manifests itself as 

a “notch” at 3,000, 4,000, or 6,000 Hz, depending on the frequency spectrum of the workplace noise and 

the anatomy of the individual’s ear [ACOM 1989; Osguthorpe and Klein 2001; Suter 2002; Schlaucha 

and Carneya 2011]. A notch in an individual with normal hearing may indicate early onset of NIHL. For 

NIOSH HHEs, a notch is defined as the frequency where the hearing threshold level is preceded by an 

improvement of at least 10 dB at the previous test frequency and followed by an improvement of at least 5 

dB at the next test frequency.

NIOSH has an REL for noise of 85 dBA, as an 8-hour TWA. For calculating exposure limits, NIOSH 

uses a 3-dB time/intensity trading relationship, or exchange rate. Using this criterion, an employee can 

be exposed to 88 dBA for no more than 4 hours, 91 dBA for 2 hours, 94 dBA for 1 hour, 97 dBA for 0.5 

hours, etc. Exposure to impulsive noise should never exceed 140 dBA. For extended work shifts NIOSH 

adjusts the REL to 84.0 dBA for a 10-hour shift and 83.2 dBA for a 12-hour work shift. When noise 

exposures exceed the REL, NIOSH recommends the use of hearing protection and implementation of a 

hearing loss prevention program [NIOSH 1998].

The OSHA noise standard specifies a PEL of 90 dBA and an AL of 85 dBA, both as 8-hour TWAs. OSHA 

uses a less conservative 5-dB exchange rate for calculating the PEL and AL. According to the OSHA 

criterion, an employee may be exposed to noise levels of 95 dBA for no more than 4 hours, 100 dBA for 

2 hours, 105 dBA for 1 hour, 110 dBA for 0.5 hours, etc. Exposure to impulsive or impact noise must not 

exceed 140 dB peak noise level. OSHA does not adjust the PEL for extended work shifts. However, the 

AL is adjusted to 83.4 for a 10-hour work shift and 82.1 dBA for a 12-hour work shift. OSHA requires 

implementation of a hearing conservation program when noise exposures exceed the AL [29 CFR 

1910.95].

An employee’s daily noise dose, on the basis of duration and intensity of noise exposure, can be calculated 

according to the formula: Dose = 100 x (C1

/T1 + C2/T2 + ... + Cn/Tn ), where Cn indicates the total time of 

exposure at a specific noise level and Tn

 indicates the reference exposure duration for which noise at that 

level becomes hazardous. A noise dose greater than 100% exceeds the noise exposure limit.
Health Hazard Evaluation Report 2011-0129-3160 Page 18

A pendix A: Occupational Exposure Limits and ealth Effects

(continued)

To calculate the noise dose using NIOSH criteria, the reference duration (Tn

be calculated using the following formula: T(min) = 480/2(L-85)/3, where L = the measured noise exposure 

level for each time period. To calculate noise dose using OSHA criteria, the reference duration (Tn

) for 

each time period must be calculated using a slightly different formula: T(min) = 480/2(L-90)/5,where L = the 

measured noise exposure level for each time period.

) for each time period must 

References

ACOM [1989]. Occupational noise-induced hearing loss. ACOM Noise and Hearing Conservation 

Committee. J Occup Med 31(12):996.

Berger EH, Royster LH, Royster JD, Driscoll DP, Layne M, eds. [2003]. The noise manual. 5th rev. ed. 

Fairfax, VA: American Industrial Hygiene Association.

CFR. Code of Federal Regulations. Washington, DC: U.S. Government Printing Office, Office of the 

Federal Register.

Earshen J [2003]. Sound measurement: instrumentation and noise descriptors. In: Berger EH, Royster LH, 

Royster JD, Driscoll DP, Layne M, eds. The noise manual. 5th rev. ed. Fairfax, VA: American Industrial 

Hygiene Association, p. 54.

NIOSH [1998]. Criteria for a recommended standard: occupational noise exposure (revised criteria 1998). 

Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and 

Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 98-

126.

Osguthorpe JD, Klein AJ [2001]. Occupational hearing conservation. Clin Audiol 24(2):403–414.

Schlaucha RS, Carneya E [2011]. Are false-positive rates leading to an overestimation of noise-induced 

hearing loss? J Speech Lang and Hear Res 54(2):679–692.

Suter AH [2002]. Hearing conservation manual. 4th ed. Milwaukee, WI: Council for Accreditation in 

Occupational Hearing Conservation.

Tak S, Davis RR, Calvert GM [2009]. Exposure to hazardous workplace noise and use of hearing 

protection devices among U.S. workers--NHANES, 1999–2004. Am J Ind Med 52(5):358–371.

p
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Appendix B: Methods

A noise dosimeter (Larson Davis, Provo, Utah, SparkTM model 706RC) was attached to the wearer’s belt, 

and a small remote microphone was fastened to the wearer’s shirt at a point midway between the ear 

and outside of the shoulder. For area noise measurements, a dosimeter was placed on each side of the 

room near the storage racks. Windscreens provided by the dosimeter manufacturer were placed over the 

microphones to reduce or eliminate artifact noise, which can occur if objects bump against unprotected 

microphones. The dosimeters were set up to collect data using different settings to allow comparison of 

noise measurement results with the three different noise exposure limits referenced in this HHE, the 

OSHA PEL and AL and the NIOSH REL (Table B1). During noise dosimetry measurements, noise levels 

below the threshold level are not integrated by the dosimeters for accumulation of dose and calculation of 

TWA noise level.

The dosimeters averaged noise levels every second. At the end of the sampling period, the dosimeters were 

removed and paused to stop data collection. The noise measurement information stored in the dosimeters 

was downloaded to a computer for interpretation with Larson Davis Blaze® software. The dosimeters were 

calibrated before and after the measurement periods according to the manufacturer’s instructions.

Area noise levels and octave band noise frequency analysis (measurement of noise in different frequencies) 

were measured with System 824 SLM real-time frequency analyzers (Larson-Davis, Provo, Utah). The SLMs 

were equipped with 0.5-inch random incidence Type 1 microphones. Noise and octave band frequency 

spectrum measurements were collected at a sample rate of 51,200 times per second and averaged eight 

times per second. The SLMs were calibrated before and after the measurement periods according to the 

manufacturer’s instructions. SLMs were mounted on a tripod at a height of approximately 5 feet.

Table B1. Dosimeter settings

Parameters OSHA AL OSHA PEL NIOSH REL

Response Slow Slow Slow

Exchange rate 5 5 3

Criterion level 90 90 85

Threshold 80 90 80
Health Hazard Evaluation Report 2011-0129-3160 Page 20

Acknowledgments and

Availability of Report The Hazard Evaluations and Technical Assistance Branch 

(HETAB) of the National Institute for Occupational Safety and 

Health (NIOSH) conducts field investigations of possible health 

hazards in the workplace. These investigations are conducted 

under the authority of Section 20(a)(6) of the Occupational Safety 

and Health Act of 1970, 29 U.S.C. 669(a)(6) which authorizes 

the Secretary of Health and Human Services, following a written 

request from any employer or authorized representative of 

employees, to determine whether any substance normally found 

in the place of employment has potentially toxic effects in such 

concentrations as used or found. HETAB also provides, upon 

request, technical and consultative assistance to federal, state, and 

local agencies; labor; industry; and other groups or individuals to 

control occupational health hazards and to prevent related trauma 

and disease.

Mention of any company or product does not constitute 

endorsement by NIOSH. In addition, citations to websites 

external to NIOSH do not constitute NIOSH endorsement of 

the sponsoring organizations or their programs or products. 

Furthermore, NIOSH is not responsible for the content of these 

websites. All Web addresses referenced in this document were 

accessible as of the publication date.

This report was prepared by Lilia Chen and Scott E. Brueck of 

HETAB, Division of Surveillance, Hazard Evaluations and Field 

Studies. Industrial hygiene equipment and logistical support 

was provided by Donald Booher and Karl Feldmann. Health 

communication assistance was provided by Stefanie Evans. 

Editorial assistance was provided by Ellen Galloway. Desktop 

publishing was performed by Greg Hartle.

Copies of this report have been sent to employee and 

management representatives at the school, the state health 

department, and the Occupational Safety and Health 

Administration Regional Office. This report is not copyrighted 

and may be freely reproduced. The report may be viewed and 

printed at http://www.cdc.gov/niosh/hhe/. Copies may be 

purchased from the National Technical Information Service at 

5825 Port Royal Road, Springfield, Virginia 22161.
Below is a recommended citation for this report:

NIOSH [2012]. Health hazard evaluation report: noise evaluation of elementary 

and high school music classes and indoor marching band rehearsals – Alabama. 

By Chen L, Brueck SE. Cincinnati, OH: U.S. Department of Health and Human 

Services, Centers for Disease Control and Prevention, National Institute for 

Occupational Safety and Health, NIOSH HETA No. 2011-0129-3160.

To receive NIOSH documents or information about 

occupational safety and health topics, contact NIOSH at:

1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

E-mail: cdcinfo@cdc.gov

or visit the NIOSH web site at: www.cdc.gov/niosh.

For a monthly update on news at NIOSH, subscribe to 

NIOSH eNews by visiting www.cdc.gov/niosh/eNews.

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