The reduction of gunshot noise and auditory risk through the use of firearm suppressors and low-velocity ammunition.

Objective: This research assessed the reduction of peak levels, equivalent energy and sound power of firearm suppressors.

Design: The first study evaluated the effect of three suppressors at four microphone positions around four firearms. The second study assessed the suppressor-related reduction of sound power with a 3 m hemispherical microphone array for two firearms.

Prevention of Noise-Induced Hearing Loss from Recreational Firearms.

In the United States and other parts of the world, recreational firearm shooting is a popular sport that puts the hearing of the shooter at risk. Peak sound pressure levels (SPLs) from firearms range from ∼140 to 175 dB. The majority of recreational firearms (excluding small-caliber 0.

Auditory risk of air rifles.

Objective: To characterize the impulse noise exposure and auditory risk for air rifle users for both youth and adults.

Design: Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit and LAeq75 exposure limit suggested by the World Health Organization (1999) for children.

Study Sample: Impulses were generated by nine pellet air rifles and one BB air rifle.

Auditory risk estimates for youth target shooting.

Objective: To characterize the impulse noise exposure and auditory risk for youth recreational firearm users engaged in outdoor target shooting events. The youth shooting positions are typically standing or sitting at a table, which places the firearm closer to the ground or reflective surface when compared to adult shooters.

Design: Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit suggested by the World Health Organization (1999) for children.

Impulse noise generated by starter pistols.

Objective: This study describes signals generated by .22 and .32 caliber starter pistols in the context of noise-induced hearing loss risk for sports officials and athletes.

Measurement of impulse peak insertion loss for four hearing protection devices in field conditions.

Objective: In 2009, the U.S. Environmental Protection Agency (EPA) proposed an impulse noise reduction rating (NRR) for hearing protection devices based upon the impulse peak insertion loss (IPIL) methods in the ANSI S12.

The influence of stuttering severity on acoustic startle responses.

Purpose: This study examined the potential impact of stuttering severity, as measured by the Perceptions of Stuttering Inventory (Woolf, 1967) on acoustic startle responses.

Method: Three groups, consisting of 10 nonstuttering adults, 9 mild stutterering adults, and 11 moderate/severe stutterering adults, were presented with identical 95-dB acoustic stimuli to elicit acoustic startle responses across 10 trials. Electromyographic recordings of orbicularis occuli activity were used to measure individual acoustic startle responses.

Jaw stretch reflexes in children.

The substantial morphological transformations that occur during human development present the nervous system with a considerable challenge in terms of motor control. Variability of skilled motor performance is a hallmark of a developing system. In adults, the jaw stretch reflex contributes to the functional stability of the jaw.