User Tools

  • hearing protection
  • wireless real-time monitoring
  • Internet of Things
  • product development
  • mechanical design
  • user experience design
  • cloud-based web app
  • Amazon Web Services

Aw8-2 +

Aw8-2 is a hearing protection device. is the associated web application. ATI created the entire system to help reduce occupational hearing loss - by providing industrial hygienists, audiologists, and safety managers with near real-time information about their clients' noise exposures. Instead of relying on coarse and infrequent area surveys, users can monitor noise exposure directly. So, if an individual client is approaching their safe noise limit, a manager can know about it immediately and take action - before hearing damage occurs.

Aw8-2 is a hearing protector, tracks noise exposure


Noise induced hearing loss (NIHL) is a major problem in military and manufacturing sectors. High performance hearing protection devices (HPD's) are available but there are not reliable systems for detecting changes in noise level that occur between regularly scheduled noise surveys. There are few means for evaluating the adequacy of a person's hearing protection, or for detecting and enforcing compliance with hearing conservation directives. Hearing loss today is not as much about a lack of intervention options, but about a lack of actionable information. Aw8-2 + changes all of that by providing timely relevant metrics.

Aw8-2 and overview illustration

  • Clients wear the earplugs in their ears and the Aw8-2 on their shirt
  • Aw8-2's collect and store sound level measurements until Wi-Fi is available
  • Wi-Fi conveys the data to
  • Managers log in to see up-to-date noise totals
  • If noise totals are too high, managers can act - before it's too late

Aw8-2 hearing protectors measure sound levels from inside and outside of the ear. So, can also help to identify common problem scenarios such as when earplugs don't fit, or when someone isn't wearing their earplugs. Aw8-2 + Noise Scenarios (PDF), link (2013-07-30)

Aw8-2 device

The Aw8-2 is a new class of personal protection product: part hearing protector, part dosimeter, part Internet device. It is first to offer wireless, real-time noise exposure monitoring. It is only the second to offer in-ear microphones (after doseBusters USA) and it is first to combine in-ear and exterior measurements to verify that earplugs are being worn properly. Aw8-2's are innovative in other ways as well:

  • No ON/OFF switch - simple, always on, always logging (except on the charger)
  • Automatic uploads - data saves over Wi-Fi so you never mess with files or cables
  • Fire and forget - setup once then see results on…no checking in or out

Design Goals

  1. Be super easy to use, demand far less admin overhead than a traditional dosimeter
  2. Be useful for military AND industry, not just the harshest environments
  3. Be first with wireless, real-time reporting to support time-critical decisions
  4. Be first with anytime, anywhere monitoring, so IH's can manage remote sites
  5. Provide objective evidence of hearing protection
  6. Be affordable, not another high-end research toy
  7. Be small and power/bandwidth efficient
  8. Be tough, not bomb-proof (expensive), but rugged


Specification Aw8-2
:check: Hearing Protection NRR 28 dB with foam earplugs, custom earplugs are also available
:check: Easy to Use No buttons, always on, always working
:check: Easy to Administer Personal issue, no need to manage check-in and checkouts
:check: Saves Automatically Uses local Wi-Fi network, no cables, no download hassles
:check: Compliance Tracking Know who wears their hearing protectors
:check: Real-Time Results Track results from anywhere, anytime on
:check: 3 Microphones In-ear left, in-ear right, and exterior
:check: Measurement Range 50 - 130 dB SPL
:check: Battery Rechargeable lithium ion (included)
:check: Battery Life 10+ hours per charge
:check: Battery Charging Time Less than 2 hours
:check: On-board Memory To store up to 5 days of data between uploads
:check: EMI hardened Designed for the flight deck, tested to 100 V/m
:check: Size 2.2“ x 2.7” x 0.7“ (57 x 70 x 19 mm)
:check: Weight 65 grams
:check: Made in the USA Designed, built and supported in the USA is a web application based on the AWS cloud computing platform. It receives streams of instantaneous sound pressure level measurements, from client-worn Aw8-2 devices, and presents cumulative noise exposure results in a clear and actionable format. The interface is arranged to give safety managers immediate access to the hearing protection statuses of all of their personnel. By default, clients at highest risk are at the top of the list. Icons and bright colors further differentiate those individuals who are close to, or have exceeded, standards-defined exposure limits.

For more in-depth analyses, the charting feature shows time histories of each microphone signal. Users can zoom and pan with mouse gestures. They can compare in-ear and exterior sound levels for a single client, or between clients. There is also a reporting tool and an export function that makes it easy to get the raw data out, for custom processing., screen images as of 2013-11-25

Screen images from, (2013-11-25)

Key Features

  • Dashboard gives real-time noise exposure results for all personnel, at a glance
  • Chart shows time history of all microphone readings
  • Calculations include Dose, TWA, and Lav metrics, for all Aw8-2 clients, over any time period
  • Calculations support all major noise dosimetry standards from OSHA, MSHA, NIOSH, Navy…
  • Export feature saves raw data as CSV files, for use in 3rd party programs
  • As a web-application is available anytime, from anywhere

Screen recording from, (2013-11-25)


US 8,848,929 - Sound Exposure Monitoring System and Method for Operating the Same

Issued Patent US8848929 Sound Exposure Monitoring System and Method for Operating the Same

US 20120321094 - Sound Exposure Monitoring System and Method for Operating the Same

A personal noise monitoring system and method for operating the same. Sound pressure data from inside the ears of a user of hearing protection device (HPD) are acquired from microphones in the HPD and reported to a master control unit. Simultaneously, the master control unit receives sound pressure data from the ambient environment in which the user is located. The data are reported to a central server for processing. The central server may use the data to determine in near real time or real time whether the user of the HPD is at risk for exposure to excess sound levels and to take remedial action while the user is still in the ambient environment.

Patent Application US20120321094 Sound Exposure Monitoring System and Method for Operating the Same



The product system has been used by Navy installations ashore and afloat as well as onsite by a major defense contractor.

Lincoln Leads the Way in Hearing Conservation (PDF), link (2013-10-19)
Thursday, July 25, 2013


Broad Agency Announcement for Warfighter Developmental Protective Clothing and Devices

SYNOPSIS: The Naval Air Warfare Center awarded this contract to develop a Noise [Dosimeter] for Personnel Noise Exposure Assessments which include[s] DNC Microphone, Pilot ANR Earplug, ANR Impulse Control, and Noise Monitor to be researched. link (2013-11-17)

Principal Investigator:

$280,228, $232,202 (2 delivery orders)
~18 months, 2011-2012

link (2013-11-17)

  • web app interacts with custom hardware, server hardware, and human users
  • project involved design of all systems: mechanical, electrical, firmware, software
  • we developed a custom file format to encoding sound level measurements to minimize on-board memory and bandwidth requirements
  • noise is the first application, but the system could be expandable to pulse-ox, dust, etc
  • simple user interface requires no/minimal training

Contract covered multiple projects - a subset of tasks involved Aw8 and