REAL-TIME DUST MONITOR FOR INDOOR AIR QUA- LITY MEASUREMENTS AND WORKPLACE EXPOSURE ASSESSMENTS FIDAS

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1 PRODUCT DATASHEET - APPLICATIONS Indoor air quality studies Workplace exposure measurements Exhaust air monitoring Emission source classification BENEFITS Continuous and simultaneous real-time measurements of multiple PM values Additional information based on particle number concentration Adjustable time resolution from > 1 s to 24 h Light source: LED with high stability and long lifetime Low maintenance, possible to verify calibration on site and reduces your operating expenses Intuitive and easy to operate - Reliable function No radioactive material and no consumables PRODUCT DATASHEET -

2 PRODUCT DATASHEET - PRESENTATION The device is a high resolution optical spectrometer used to classify atmospheric aerosols into several size classes. The measures in real-time the conventional PM-10, PM-4.0, PM-2.5 and PM-1.0 fractions. Furthermore, it stores every second the number of particles in each of the 256 measurement channels. For use on stations that measure atmospheric pollutants, has all the features needed to run automatically and transmit data remotely (some of these features are optional depending on model): PM-2.5, PM-10 and Total Dust sampling heads Internal collection filter holder to compare the concentration value measured to the collected mass concentration Vacuum pump with a high flow rate: 5 lpm Atmospheric probes: pressure, temperature, humidity, wind speed and direction, intensity and type of precipitation Real-time correction of the effects of humidity on the particle size IADS system for real-time regulation of the relative humidity of the sample Storage every second of data generated by the spectrometer and its accessories Remote access via web server Separate data analysis software to be used remotely «In situ» calibration by the user PRODUCT DATASHEET -

3 PRODUCT DATASHEET - MEASURING PRINCIPLE The counting of the particles is based on the fact that the particles move one by one across an optically defined measurement volume, whose light intensity is uniform. The spectrometer uses the light scattered by the dust to determine their size. The principle of counting particles based on the fact that the particles pass through one by one the light beam and the light density is homogeneous in the measuring volume. This principle is widely used for particle counting, but Palas uses several techniques to overcome the artefacts commonly encountered on laser diode particle counters: Use of a white light source with 90 detection The device uses an LED emitting a white radiation of very high power. The scattered light is detected at 90 from the incident beam. This technique provides a clear calibration curve for different refractive indices, which is not the case when a laser diode is used. The 90 detection allows an unambiguous and accurate measurement in the µm range, which is not the case for 180 light-detecting cells. Homogeneous illumination of the measurement volume by T-shaped diaphragm The measurement of the size of a particle passing through a light beam can only be accurate if the beam intensity is uniform over the entire measurement volume. The Gaussian power distribution of a laser beam cannot obtain sufficient homogeneity throughout the measurement volume and induces errors in assessing the size of the edges of the beam called «border zone error.» PRODUCT DATASHEET -

4 PRODUCT DATASHEET - To avoid this mistake, the Fidas uses a T-shaped diaphragm that eliminates several artefacts (see Fidas technical notes) geometrically separating homogeneous areas of the beam from heterogeneous border areas. This T shape also allows real time recalculation of the coincidence error which occurring at high concentrations. The beam inhomogeneity errors and coincidence errors are then easily corrected or detected when measuring the duration of pulses generated by the photo detector: Rejection of too short pulses emitted by the particles circulating in the border area. This avoids underestimating the size of the particles. An alarm signals when pulses are too long: it is symptomatic of the simultaneous presence of several particles in the measurement volume (coincidence errors cause an underestimation of the particle concentration and an overestimation of the particle size.) SPECTROMETER The is available in different versions depending on the application it is required for: Desktop housing version, easily transportable, for use in a shelter or indoor air IP65 housing version for outdoor installation spectrometers are designed for automatic unattended operation and automatically restart in case of power failure. The data is stored every second and can be accessed remotely through RS232 output or Internet. Evaluation software can examine and process data remotely regardless of the analyser. PRODUCT DATASHEET -

5 FICHE PRODUIT - SPECIFICATIONS LIGHT SOURCE LED MEASURING PRINCIPLE RECORDED DATA MEASUREMENT RANGE Optical light-scattering PM-1, PM-2.5, PM-4, PM-10, TSP, CN, particle size distribution - Measurement range (number): particles/cm 3 - Measurement range (size): µm (3 sizes) - Measurement range (mass): µg/m 3 DIMENSIONS WEIGHT POWER TIME RESOLUTION FLOW RATE x 450 x 320 mm, 19» compatible, 4 HE, 84 TE 9.3 kg - Power consumption: 100 W - Power supply: V, Hz 1 s - 24 h 5 lpm TEMPERATURE OPERATING DATA ACQUISITION HOUSING -10 to +50 C Digital, 20 MHz processor, 256 raw data channel User interface touch screen, 800 x 480 pixels, 7» Table housing, optionally with mounting brackets for rack-mounting DATA LOGGING STORAGE 4 GB CHANNELS 64 (32/decade) Réf.F108 V1 DOMAINE TECHNOLOGIQUE - IMMEUBLE HERMES - 4, RUE RENE RAZEL SACLAY - FRANCE l +33 (0) info@ecomesure.com l