Gregory Flamme

Gregory Flamme
Stephenson & Stephenson Research & Consulting (SASRAC)

About

93
Publications
37,786
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1,094
Citations
Citations since 2017
43 Research Items
654 Citations
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2017201820192020202120222023020406080100120
2017201820192020202120222023020406080100120
2017201820192020202120222023020406080100120
Introduction
Skills and Expertise

Publications

Publications (93)
Presentation
Full-text available
No PDF available ABSTRACT The assessment of the risk posed by firearm noise is complicated by the divergence in the allowable numbers of rounds (ANORs) returned by the available damage-risk criteria (DRCs) for impulsive noises. The ANORs returned by DRCs are strongly correlated but wide differences exist in absolute ANORs. Some firearms have suppre...
Presentation
Full-text available
The American National Standard, ANSI S12.42-2010, specifies the impulse peak insertion loss (IPIL) for a hearing protection device (HPD) using an acoustic test fixture (ATF) over a range of impulse levels nominally at 132, 150, and 168 dB peak sound pressure level (dB pSPL). The GRAS 45CB ATFs have ear simulators fitted with GRAS 40BP microphones (...
Presentation
Full-text available
No PDF available ABSTRACT High-level impulse noise exposure from small caliber firearms presents a significant risk of noise induced hearing loss (NIHL) for an unprotected ear. The most common method to reduce the level of noise is to provide hearing protection to both the shooter(s) and potential observers such as firing range instructors or bysta...
Article
Middle ear muscle contractions (MEMCs) are most commonly considered a response to high-level acoustic stimuli. However, MEMCs have also been observed in the absence of sound, either as a response to somatosensory stimulation or in concert with other motor activity. The relationship between MEMCs and non-acoustic sources is unclear. This study exami...
Article
No PDF available ABSTRACT Starting in the 1970s, Larry Royster and his colleagues conducted a series of large-scale studies demonstrating that people with non-Hispanic Black race/ethnicity had better hearing sensitivity than their non-Hispanic White counterparts. One major outcome of this work was the adoption of specific age-related hearing sensit...
Article
Full-text available
No PDF available ABSTRACT High-level impulse noise has been a significant source of hearing loss among active duty military personnel, veterans, law enforcement and recreational firearm users. The development of standards for estimating the risk of hearing loss due to such exposures is complicated by a lack of human exposure data. Following World W...
Article
No PDF available ABSTRACT The maximum tolerable exposures returned by damage-risk criteria for impulsive noise are often designed to protect the population to the 5th percentile most susceptible exposed person. To protect human research volunteers, estimates of this location on the distribution must be estimated rather than measured directly. In th...
Presentation
Full-text available
These slides are from a workshop we presented at the 2020 NHCA meeting in Destin Fl
Article
Objective: In occupational hearing conservation programmes, age adjustments may be used to subtract expected age effects. Adjustments used in the U.S. came from a small dataset and overlooked important demographic factors, ages, and stimulus frequencies. The present study derived a set of population-based age adjustment tables and validated them us...
Article
Full-text available
Firearm suppressors reduce the muzzle blast of a gunshot through a series of baffles contained in a canister. The American National Standards Institute has no firearm suppressor testing standards. A recent NATO test standard, AEP 4875, ignores the contribution of the ground reflection at the shooter's ears and is not representative of how firearms...
Article
Full-text available
Middle ear muscle contractions (MEMC) can be elicited in response to high-level sounds, and have been used clinically as acoustic reflexes (ARs) during evaluations of auditory system integrity. The results of clinical AR evaluations do not necessarily generalize to different signal types or durations. The purpose of this study was to evaluate the l...
Article
Full-text available
Background: Prior studies have found that rescue and recovery workers exposed to the 9/11 World Trade Center (WTC) disaster have evidence of increased persistent hearing and other ear-related problems. The potential association between WTC disaster exposures and post-9/11 persistent self-reported hearing problems or loss among non-rescue and recov...
Article
Objective: To determine if World Trade Center (WTC) exposure is associated with hearing loss. Methods: Logistic regression to evaluate the immediate impact of WTC exposure and parametric survival analysis to assess longitudinal outcomes. Results: Those arriving on the morning of 9/11/2001 had elevated odds of low-frequency (odds ratio [OR]: 1....
Presentation
Full-text available
Sound from referee whistles at sporting events is usually relatively short in duration (<250 ms) but generated at relatively high levels (>110 dB SPL). Damage risk criteria (DRC) that categorize potentially harmful sounds are usually meant for either continuous or impulsive noise. These types of whistle sounds are better categorized as impulsive. M...
Presentation
Full-text available
Cannons, small firearms, and starter pistols are sometimes used with blank charges during sporting events, ceremonies, and historical re-enactments. The sound levels produced by such devices are not widely known, and it is possible that the personnel discharging them could underestimate the potential risk to hearing. Depending upon the proximity to...
Presentation
Full-text available
Referee whistles have been suggested as a significant contributor to noise-induced hearing loss. Thirteen models of sport whistles were tested for sound power with a 3-meter hemispherical array of 19 microphones. The whistler produced nine tweets of low, medium, and high effort with two samples of each whistle model. Sound power levels ranged betwe...
Presentation
Full-text available
This paper compares seven damage risk criteria for impulses measured with small caliber firearms. The conclusions, at least for these data are that the DRCs are largely measuring similar results, the question is what is the acceptable level of hazard before hearing loss is incurred.
Presentation
Full-text available
This paper examined the potential for muscular activity to influence the activation of the middle ear muscle contraction
Presentation
Full-text available
This paper examines the current age correction tables used by OSHA and looks at the NHANES data 25% for subjects in good health and derives new age-correction values. These values are compared to the longitudinal data from a noise exposed population of fire fighters and first responders involved with the World Trade Center Project.
Article
Objective: Assessment of the auditory risk associated with sound from ballistic N-waves produced by a rifle bullet. Design: Acoustical recordings of ballistic N-waves passing through a microphone array at 6.4 metres down range were analysed to determine (a) the trajectory of the bullet, (b) the distance between the trajectory and each microphone (l...
Article
Objectives/Hypothesis To investigate factors associated with hearing impairment (HI) in adolescent youths during the period 1966–2010. Study Design Cross‐sectional analyses of US sociodemographic, health, and audiometric data spanning 5 decades. Methods Subjects were youths aged 12 to 17 years who participated in the National Health Examination S...
Technical Report
Full-text available
The Auditory Hazard Assessment Algorithm for Humans (AHAAH) employs the response of the Middle Ear Muscle Contraction (MEMC) as a protective mechanism against high-level impulse noise. The “warned” option in the AHAAH model assumes that the MEMC is conditioned to activate prior to the noise when a person fires a weapon. This report details procedur...
Presentation
Full-text available
A bullet traveling at supersonic speeds produces a ballistic shock-wave that is N-shaped (N-wave) with properties that are determined by the speed and dimensions of the projectile. The sound levels of these N-waves can be hazardous, and can be comparable to the blast wave received at the shooter’s ear. The present study was undertaken to assess the...
Presentation
Full-text available
Suppressors use a combination of baffles and ports within a canister at the end of a firearm to disrupt the high-pressure shock wave that follows the expulsion of the projectile. This study evaluated fourteen different firearms with and without a suppressor. Different loads of ammunition were used to vary the speed of the projectile. For ten of the...
Presentation
Full-text available
The Auditory Hazard Assessment Algorithm for Humans (AHAAH) employs the response of the Middle Ear Muscle Contraction (MEMC) as a protective mechanism against high-level impulse noise. The Warned condition in the AHAAH model assumes that the MEMC is conditioned to activate prior to the noise when a person fires a weapon. This study evaluated three...
Poster
Full-text available
Middle ear muscle contractions (MEMC) are often included as a protective mechanism in damage-risk criteria for impulsive noise. Explanations for inclusion of MEMC emphasize the role of acoustic elicitors, though it is known that non-acoustic stimuli such as head/neck motor activity also elicit MEMC. Studies rarely monitor motor activity at the time...
Poster
Full-text available
Damage-risk criteria frequently include middle-ear muscle contractions (MEMC) as a protective mechanism against impulsive noise. In addition to acoustic elicitors, activities such as chewing and swallowing have also been reported to elicit MEMC. Careful examination of the various acoustic and non-acoustic sources of MEMC is necessary to properly as...
Article
Full-text available
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 microphon...
Article
Full-text available
Objective: The objective of this study is to determine whether acoustic reflexes are pervasive (i.e. known with 95% confidence to be observed in at least 95% of people) by examining the frequency of occurrence using a friction-fit diagnostic middle ear analyser. Design: Adult participants with very good hearing sensitivity underwent audiometric...
Article
Full-text available
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 0.17 and 0.22 rifles and air rifles) generate between 150 and 165...
Article
Objective: To examine the association between 9/11-related exposures and self-reported hearing problems among 16,579 rescue/recovery workers in the World Trade Center (WTC) Health Registry. Methods: Using Registry Waves 1 (2003 to 2004) and 2 (2006 to 2007), we modeled the association between two metrics of 9/11-related exposures and hearing dif...
Article
In Reply We thank Dr Fuller-Thomson for her suggestion. Prior publications have found associations between hearing impairment (HI) and blood lead levels (BLL) and cadmium.¹,2 If associations exist, it is unknown what proportion of HI in the population may be attributable to lead and/or cadmium or other heavy metals. Heavy metal exposures co-occur w...
Article
Full-text available
Recreational firearm use is a popular leisure-time activity in the United States today. Millions of Americans of all ages enjoy shooting sports including target practice, competitive shooting, and hunting. While participation in the shooting sports can be an enjoyable recreational pursuit, it can also put an individual at risk for noise-induced hea...
Presentation
Full-text available
As a companion paper to the sound power evaluation of referee whistles, we conducted measurements of the whistles in the laboratory. Intraoral pressure seemed to maintain a linear relationship with the RS amplitude.
Presentation
Full-text available
The paper describes the evaluation of 13 models of referee whistles evaluated for peak levels, 8-hour equivalent A-weighted energy and sound power at an outdoor test site. Levels ranged between peak sound pressure levels of 70 - 105, 85 - 117 and 102 - 120 dB for three different levels of blowing effort (Low, Medium and High). The LAeq8 values rang...
Article
Importance: As the US population ages, effective health care planning requires understanding the changes in prevalence of hearing loss. Objective: To determine if age- and sex-specific prevalence of adult hearing loss has changed during the past decade. Design, setting, and participants: We analyzed audiometric data from adults aged 20 to 69 y...
Presentation
Full-text available
High-level sounds can elicit middle ear muscle contractions (MEMC), which are commonly known as acoustic reflexes. Tactile stimulation to the face can also elicit MEMC, and it is plausible that MEMC could co-occur with voluntary eye closure gestures. In this paper, we shall present preliminary MEMC results from human volunteers receiving controlled...
Article
Objective: To determine whether acoustic reflexes are pervasive (i.e. sufficiently prevalent to provide 95% confidence of at least 95% prevalence) and might be invoked in damage-risk criteria (DRC) and health hazard assessments (HHA) for impulsive noise. Design: Cross-sectional analyses of a nationally-representative study. Study sample: National H...
Article
Full-text available
Department of Defense Design Criteria Standard Noise Limits (MIL-STD-1474E), published in 2015, is a standard developed for the acquisition of military materiel specifies the maximum permissible noise levels produced by military systems and the test requirements for measuring these levels. It is intended for use by equipment designers and manufactu...
Presentation
Full-text available
Unprotected or under-protected exposure to high-level acoustic impulses and consequent hearing loss has broad consequences regarding survivability and operational effectiveness, retention of a fit force, force readiness, service-related disability costs for hearing injuries, and the acquisition and maintenance of assistive technologies. Assumptions...
Presentation
Full-text available
The presentation was a progress report on the research conducted to assess the effect of the middle ear muscle contraction in humans in response to an impulse noise. The presentation reviews the prevalence of acoustic reflex in humans as reported in the National Health and Nutrition Examination Survey and it reports on the measurements of the MEMC...
Conference Paper
Full-text available
Law enforcement, security, and military personnel train with small-caliber firearms that present a significant risk of noise induced hearing loss for the operator and range instructors. Measurements of three rifles and one pistol equipped with suppressors were conducted at an outdoor firing range using subsonic and supersonic ammunition. Suppressed...
Presentation
Full-text available
Gunshot sound pressure levels are commonly measured using commercial sound level meters. The performance of commercial SLMs are compared to a field research system reference. Performance was considered in terms of peak SPL, LAeq8 and damage risk indices. Impulses were generated by a Colt AR-15 and measurements were obtained at 5 reference level loc...
Article
Full-text available
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...
Article
Full-text available
The acoustic reflex is a contraction of the middle ear muscles in response to high-level sounds. Acoustic reflexes are invoked as a protective mechanism in some damage-risk criteria (DRC). However, acoustic reflexes are not always observed among people without auditory dysfunction, and should not be included in DRC unless there is 95% certainty tha...
Article
Full-text available
The acoustic reflex is an involuntary contraction of the middle ear muscles in response to a variety of sensory and behavioral conditions. Middle ear muscle contractions (MEMC) have been invoked in some damage-risk criteria for impulsive noises for over 40 years and one damage-risk criteria proposes that MEMC precede the impulse for a warned listen...
Article
Full-text available
Objective: This study examined differences in thresholds obtained under Sennheiser HDA200 circumaural earphones using pure tone, equivalent rectangular noise bands, and 1/3 octave noise bands relative to thresholds obtained using Telephonics TDH-39P supra-aural earphones. Design: Thresholds were obtained via each transducer and stimulus conditio...
Article
Full-text available
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 ch...
Article
Full-text available
Objective: To estimate the short-term variability and correlates of variability in pure-tone thresholds obtained using audiometric equipment designed for occupational use, and to examine the justification for excluding 8 kHz as a mandatory threshold in occupational hearing conservation programs. Method: Pure-tone thresholds and other hearing-rel...
Article
Full-text available
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. Design: Acoustic comparison of impulses generated from typical .22 and .32 caliber starter pistols firing blanks were made to impulses generated from comparable firearms fir...
Data
Small caliber firearms (rifles, pistols and shotguns) are commonly used at outdoor firing ranges for training in shooting skills, job qualification and for recreation. Firearm noise from fifty-four weapons was measured at an outdoor range in the near field (6 meters and closer) of the weapons using a radial array of 18 microphones centered on the s...
Article
The objectives of this study were to examine the prevalence of hearing loss in a sample of sports officials and estimate the duration of whistle use required to reach a permissible 8-hr 100% noise dose. We conducted an online survey of 321 sports officials regarding their exposure to whistle noise and symptoms of hearing loss and tinnitus, and we a...
Conference Paper
Full-text available
Small caliber firearms (rifles, pistols and shotguns) are commonly used at outdoor firing ranges for training in shooting skills, job qualification and for recreation. Firearm noise from fifty-four weapons was measured at an outdoor range in the near field (6 meters and closer) of the weapons using a radial array of 18 microphones centered on the s...
Article
Full-text available
Identify the distribution of typical noise levels present in daily life and identify factors associated with average sound levels. This was an observational study. Participants (N = 286) were 20 to 68 year old men and women, drawn from the general population of Kalamazoo County, Michigan. A total of 73 000 person-hours of noise monitoring were cond...
Article
Full-text available
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 S12.42-2010 standard. This study tests the ANSI S12.42 methods with a range of hearing protection devices measured in field conditions. The meth...
Article
This project was conducted to characterize the noise exposure of adolescents living in rural and agricultural environments. From May to October, 25 adolescents ages 13 through 17, living either on a farm or a rural nonfarm, were enrolled in the study. Subjects received training on the correct operation and use of personal noise dosimeters and the p...
Presentation
Full-text available
Acoustic test fixtures (ATF) for testing the impulse peak insertion loss (IPIL) of a hearing protector are described by American National Standard ANSI S12.42-2010. The self-insertion loss, ear simulator design (canals, microphone, and temperature), hardness of the area surrounding the pinna, and the anthropometric shape of the head has been specif...
Presentation
Full-text available
In 2009, the US Environmental Protection Agency proposed an impulse noise reduction rating (NRR) for hearing protection devices. The impulse NRR is based the American National Standard, ANSI S12.42‐2010, and requires measurements with an acoustic test fixture for three ranges of impulse noises: 130–134, 148–152, and 166–170 dB peak SPL. Five protec...
Article
Cumulative distributions of audiometric pure-tone thresholds for a non-occupationally noise-exposed population vary with demographic characteristics (e.g. gender, ethnicity, age), tested ear, and stimulus frequency. However, commonly-used audiometric databases either do not take these differences into account, or account for them using data not eas...
Article
Full-text available
What is the risk of hearing loss for someone standing next to a shooter? Friends, spouses, children, and other shooters are often present during hunting and recreational shooting activities, and these bystanders seem likely to underestimate the hazard posed by noise from someone else's firearm. Hunters use hearing protection inconsistently, and the...
Article
Sports officials commonly use a .22 caliber starter pistol at athletic events to generate a loud impulse sound to signal the start of the event (i.e. race) has started (Figure 1). Acoustic comparisons of the impulses generated from a typical .22 starter caliber pistol (Italian Model 314) firing blank ammunition were made to impulses generated from...
Article
Full-text available
Recreational use of firearms in the United States is commonplace. There are 28 x 10(6) Americans who consider themselves hunters and 13 x 10(6) went hunting in 2000. Participation in the shooting sports, without the use of properly worn hearing protection, exposes the involved persons to high levels of impulsive noise which may cause hearing loss a...
Article
Firecrackers are common impulse noise exposures in the United States. In this study, impulses produced outdoors by consumer firecrackers were recorded, described, and analyzed with respect to the amount of the auditory risk they pose to the unprotected listener under various listening conditions. Risk estimates were obtained using three contemporar...