3M eg4 Free field setting microphone, Hearing Conservation HC Hertz Hz, Lavg Average Level, Lep,d

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Appendix B

Glossary of Terms

Field Calibration (vs. Factory Calibration), pre-calibration, post-calibration

To be sure the dosimeter is functioning within specified tolerance limits, it should be returned to the factory annually for a factory recalibration. To verify that the dosimeter is measuring properly during normal use, field calibrations should be performed. Pre-calibration is performed prior to any data being recorded by the dosimeter. During a pre-calibration, the dosimeter level may be adjusted to match the calibrator output level. Post-calibration is a simple verification that the instrument has remained in calibration throughout the measurement period.

Free field setting (microphone)

Measurements made in an area without sound reflections, diffractions and absorptions caused by nearby objects (including the operator). Sound waves are free to spread out continuously, like ripples on a pond, without reflection. When making free field measurements with a dosimeter set up for use as a sound level meter, the microphone is typically pointed directly at the sound source.

Hearing Conservation (HC)

The Occupational Safety and Health Administration (OSHA) and Mine Safety and Health Administration (MSHA) provide regulatory standards for hearing conservation programs. In addition, the American Conference of Governmental Industrial Hygienists (ACGIH) provides industrial standards for hearing conservation programs. http://www.osha.gov/ , http://www.msha.gov/ , http://www.acgih.org/home.htm

Hertz (Hz)

Unit of vibration frequency in cycles per second.

Lavg (Average Level)

Lavg is the average sound level measured over the run time. This becomes a bit confusing when thresholds are used. Any sound below the threshold is not included in this average. Remember that sound is measured in the logarithmic scale of decibels therefore the average cannot be computed by simply .adding the levels and dividing by the number of samples. When averaging decibels, short durations of high levels can significantly contribute to the average level. Example: Assume the threshold is set to 80 dB and the Exchange Rate is 5 dB (the settings of OSHA’s Hearing Conservation Amendment). Consider taking a one-hour noise measurement in an office where the A-weighted sound level was typically between 50 dB and 70 dB. If the sound level never exceeded the 80 dB threshold during the one hour period, then the Lavg would not indicate any reading at all. If 80 dB was exceeded for only a few seconds due to a telephone ringing near the instrument, then only those seconds will contribute to the Lavg resulting in a level perhaps around 40 dB (notably lower than the actual levels in the environment).

Lep,d

Daily personal noise exposure level.

053-644, Rev H

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eg4

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Contents 3M The Edge Personal Noise Dosimeter EdgeTable of Contents Time history…………………………………………………………………………………………………… Setting-up the Edge via DMSReplacing microphone and windscreen Stopping a studyViewing measurements on the display Technical SupportINDEX………………………………………………………………………………… Physical attributes of EdgeDock1 and EdgeDock5List of Tables List of FiguresEdge and dosimetry DosimetryIllustration of how the dosimeter operates and processes Noise dosimeterWhat do the standards say? Range of soundApplications of the Edge View your results via DMS Setting-up your dosimeter parameters for your noise studiesNoise assessment steps Running your studiesEdge Model Parameter setup screen for eg4Identifying your equipment Checking the equipmentTurning on LED indicatorTurning off LED indicators explainedDisplay and keypad DiagramDocking station functionality 3MTMDetection Mangement Software DMSLoading EdgeDock1 or EdgeDock5 Docking station componentsEdgeDock1 and EdgeDock5 components  Powering EdgeDock1 or EdgeDock5 Powering EdgeDock1 or EdgeDock5Charging your dosimeter  How to chargeStoring the dosimeter Mounting the docking station to a wallNoise studies Understanding what data is storedTime history Summary dataLogging Views on the EdgeViews on Explanation Definitions of data log values and viewsDosimeter views and definitions Response Level WeightingViews on Explanation Edge DoseDosimeter measurement descriptors/variants Descriptors Variants Lmax variantsCommunicating & downloading data DockingNew Hardware wizard for Edge Dock Customizing set-up parameters in DMSDosimeter screen Dosimeter settingDosimeter fields explained for the Edge Edge dosimeter settingsEdge display screen Display settingEdge security setting Security settingEdge auto run screen Auto Run setting10 Edge firmware update screen Firmware update11 Saving and sending Edge setups Saving and sending/setting configurationsQuick Help List typical dosimetry session Overview of running a study How to attach the dosimeter Windscreen and maintenancePositioning the Edge on your shirt  Checking battery power Checking battery power Calibrating the dosimeter Calibrating Reset Resetting the dosimeter Contrast Setting contrast on dosimeterOn/off/enter button Running studies  How to run a noise studyStarting a run Indicators i.e., run, stop, battery, and OL Indicators/Icons on the display How to stop a noise study Indicator Icon ExplanationLocking or securing your dosimeter during run Viewing measurements on the display Viewing measurements Unlocking  How to lock or secure How to unlock Locking or Securing Downloading Downloading dataDMS start screen  Selecting and viewing data Viewing data and data finderExample of Edge Report in DMS Report ViewPanel layout view viewing the data in charts and graphs Panel Layout Viewcharts/graphsTechnical Support LED indicator disable/enableAttaching/Detaching Replacing microphone and windscreen Attaching/Detaching the windscreen and microphone Hard Hat Attachment kit Hard Hat Attachment KitStandards Mechanical characteristicsEnvironmental effects Electrical characteristicsUser Interface Physical attributes of EdgeDock1 and EdgeDock5 EdgeDock1 and EdgeDock5Types MeasurementsMeasurement parameters Auto-Run CommunicationsSpecial functions SecurityEdge Block Diagram Edge Block Diagram Appendix B Contacting 3M 3M ServiceWarranty Service Department and Technical Support 1 800Background Noise, effects Glossary of TermsCrest Factor Combining Noise sourcesCriterion Level CL Exchange Rate ER also known as the Doubling Rate Criterion TimeDecibel dB DoseLep,d Free field setting microphoneHearing Conservation HC Hertz Hz Lavg Average LevelMeasurement Range Leq Equivalent LevelLogging Maximum Level LmaxResponse Time PEL Permissible Exposure LevelProjected Time Random incidence microphoneThreshold TWA Time Weighted AverageUpper Limit UL Weighting A, C, Z, etcWindscreen Measurement equations Index Running studies About Us About 3M Personal Safety
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