1 IntroductionThe DS300 noise dosimeter is a measuring instrument allowing measurement of noise exposure at workstation. Itsadvanced features make easier the investigation to determine and reduce noise pollution:➢ frequency analysis by octave band for an optimal choice of protections➢ two-channel dosimeter for simultaneous measurement of exposures suffered by the ears➢ audio recording of noise sources on thresholds for a better identificationIn accordance with international standards, DS300 instrument calculates values usually used to compare with exposureregulatory values.Thanks to its memory, DS300 instrument stores measurement event timers which are then transferred to a computer andprocessed with LDS23 software, supplied with the instrument.LDS300 software supplied as option allows an analysis more detailed as per NF EN ISO9612: 2009 standard.In addition, this noise dosimeter has a classical sound level meter and analyzer integrating-averaging function for a 1stestimation of the noise environment of the workstation.1.1 PresentationDS 300 comes in the shape of a little case with ergonomics forms. It can be easily positioned on the belt or in a cloth pocketof people at their work station. the microphone at the end of extension is fixed thanks to a kit specially designed to minimizeperturbations created by chocks or cloth frictions.Measurements are stored in a microSD card memory of big capacity giving the whole an almost unlimited measurementcapacity.With its graphic backlighted LCD screen, DS300 is also a classical sound level meter and an integrating-averaging analyzerfor a fast noise estimation at workstation.During measurement, if necessary, it can advised people about levels through a two-coloured light.1.2 Main featuresNoise dosimeter and classical sound level meter and integrating-averaging analyzer with graphical backlighted LCD screenwith:• microphone with extension type electret of diameter 3/8'' (9.52 mm) of little size allowing a reliable fixation• 2 measurement channel: “right ear” side and “left ear” side (microphone and fixing kit for channel 2 as option)• 3 dynamic ranges:- in running mode, one measurement channel: 40-140 dB range- in running mode, two measurement channels: 40-120 dB or 60-140 dB ranges• Simultaneous measurement of Leq and LpK:- Leq: with A and C weightings and by octave band filters from 63 Hz to 8 kHz- LpK: with C or Z weightings• Management of overange of peak pressure levels 135-137-140 dB• Audio recording on thresholds of noise sources• Delayed and/or repetitive measurement start• Keyboard protection during measurement and against unwanted stops• Active or inactive LCD screen, visual alarms• Calculation and results in accordance with NF EN ISO9612: 2009 standard• Storage capacity: 99 event timer of more 24h eachLi-Ion battery for a battery-life better than 28 hours (according measurement programming). All of the setting of DS300 isdirectly performed with the keyboard or with the LDS300 software.4