Background Noise:

Classroom, Clinic and

(Research) Lab

Jill Raney, Ph.D.

April 11, 2014

University of Connecticut

Overview

Presence of background noise in

classrooms

Standards for Classroom Acoustics

Measuring impact of background

noise

Interventions

What is current research telling us.

Distance (Speaker to the listener )

–Double the distance, decrease signal by 6

dBReverberation –Persistence of the reflected sounds after

the original sound is produced. Longer

time greater the difficulty.

Noise –Greater the background noise the

poorer the Signal/Noise ratio (S/N)

Classroom Acoustic

Standards2002 - American National Standards Institute (ANSI)

created the, Acoustical Performance Criteria, Design

Requirements and Guidelines for Schools standard (ANSI

S12.60-2002). Standard developed in a effort to create a

classroom environment that optimizes speech

understanding.

2004 - American Speech-Language-Hearing Association's

(ASHA) endorsed the ANSI standard and recommended

the following criteria for classroom acoustics:

• Unoccupied classroom levels must not exceed 35

dBA

• The signal-to-noise ratio (S/N) should be at least

+15 dB at the child's ears.

• Unoccupied classroom reverberation not longer

than 0.6 seconds in smaller classrooms or 0.7

seconds in larger rooms

Clinic

Auditory Skill Development: Speech understanding in background noise

Children are not “little adults”.

Elliot, L. (1979). Performance of

children aged 9 to 17 years on a test

of speech intelligibility in noise using

sentence material with controlled

word predictability. Journal of the

Acoustical Society of

America, 66, 651-653.

Which children have difficulty

understanding speech in

background noise? Most!

• Normal hearing

• Hearing loss

• Sensorineural

• Conductive

• Unilateral

• Central Auditory Processing Disorder (CAPD)

• Aspergers

Some of the Available SIN

Tests• Words-in-Noise Test (WIN) (Wilson, 2003;

Wilson & McArdle, 2007)

• Quick Speech-in-Noise Test (QuickSIN)

(Killion et al., 2004)

• Hearing in Noise Test (HINT) (Nilsson et

al., 1994)

• BKB-Speech in Noise Test (BKB-SIN)

(Etymotic Research, 2005)

• Listening in Spatialized Noise - Sentences

Test (LiSN-S) (NAL – National Acoustic

Laboratories)

Speech-In-Noise (SIN) Testing:

Quantify the amount of

difficulty.

Stimuli: Digits

Words

Sentences

Noise: Speech-spectrum

Cafeteria

Multi-talker babble

Presentation: Modified Live-Voice (MLV)

Recorded

What can we do?

Improve the S/N

• Decrease the level of the noise (N)

• Increase the level of the signal (S)

FM - Phonak

iSense

Inspiro

Practice

Auditory Training Programs

LACE - Listening And Communication

Enhancement (Neurotone)

(LiSN-S)- Listening in Spatialized Noise

– Sentences Test (National Acoustics

Lab)

Lab - Why is noise detrimental to

speech understanding?

Dr. Nina Kraus’ Work

Audiology Online – From20Q with Gus Mueller (7/13)

Marion Downs Lecture in

Pediatric Audiology (AAA, 2014)

“Biological Assessment in

Audiology: Spotlight on Auditory

Processing and Hearing in

Noise.”

Presented by Dr. Nina Kraus

Does FM Use and Training

Work?

Summary

Presence of background noise in

classrooms

Standards for Classroom Acoustics

Measuring impact of background

noise

Interventions

What is current research telling us.

As Helen Keller said,

“Blindness separates us

from things but deafness

separates us from

people."

Thank you…