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Calibration - do it right!
To calibrate means to compare. During the calibration the measurement devices under test are compared to a reference measurement device. It should be noted that in all device characteristics the reference measurement device should be better than the tested measurement devices. It goes without saying, only calibrated measurement devices provide reliable and comparable results. ”In practice however, users often don’t know how the calibration of their particle counters was performed, so Palas® Managing Director Leander Mölter. A calibration certificate is available for each instrument, but the user often has no knowledge, on which basis the calibration was performed. Therefore, so Mölter, all devices have to be calibrated under the same conditions, if the results should be reliable and comparable. “This has led us to develop a new calibration system on the basis of our recently developed Reference Aerosol distribution System RAS 3000, with which the user can determine on site the counting efficiency differences of its particle counters in relation to a reference measurement device in an easy, fast and inexpensive way.
Measurement principles such as counting that is used in optical particle counters (OPCs) or optical aerosol spectrometers (OAS) offer the advantage, that they can determine the particle size and the particle concentration simultaneously. Today various manufacturers are offering different OPCs and OAS in various technical designs for different applications. OAS for example are used to measure the particle size distributions of aerosols, sprays or for the characterization of test aerosols, for filter testing and for the measurement of atmospheric aerosols. Here, Palas® offers the welas® digital and the Promo® systems, which can determine directly and reliably the particle size distribution in high particle concentrations up to 106 P/cm3 without dilution systems. OPCs have been developed for the characterization of cleanrooms. These devices have to determine reliably rather few incidents in a short time. Therefore OPCs often have a high suction volume flow of 28.3 l/min up to 50 l/min. By comparison, OAS have a lower suction volume flow of approximately 0.28 l/min to 5 l/min. The requirements of an OPCs for the determination of the particle size distribution are less demanding in comparison to an OAS. OPCs have been developed further and optimized for various applications. Various OPCs - with their appropriate device characteristics - are used for the verification or classification of cleanrooms into various cleanroom classes.
ISO 21501-1 defines quality characteristics
For the comparability of various, worldwide available OPCs, objective quality characteristics are necessary. These quality characteristics have been defined approximately three years ago in the standard ISO 21501-1. This standard defines the counting efficiencies, the size resolution capacity, the size classification accuracy, the zero counting rate as well as the maximum measurable particle number concentration, which is necessary for a coincidence-free particle measurement.
The quality of an OPC, such as the lower detection limit, the number of size classes, the exact volume flow and the maximum measurable particle concentration, is decisively influenced by the quality of the optoelectronic components, e.g. the light source, the angle-dependent light scattering and the clearly defined calibration curve. An important characteristic is the counting efficiency, which informs about how many particles are counted in comparison to a reference measurement device.
RAS 3000 for the calibration of the counting efficiencies of OPCs
With the new Palas® RAS 3000 the counting efficiency differences between up to six OPCs and up to five OPCs in comparison to a reference measurement device can be determined fast, reliable and inexpensive. The time for calibration is typically less than one hour.
The RAS 3000 consists of an aerosol generator with very low number concentration output and an aerosol distribution system with six aerosol outlets and six sampling cylinders. At each of the six aerosol outlets, the same number concentration ± 3 % is provided. If no clean, particle free pressurized air with a constant volume flow is available on site, Palas® recommends to use the ACA 1000 (adjustable clean airstation), which delivers a steady and high volume flow of e. g. 180 l/min ± 1 %.
The RAS 3000 provides defined, fast, reproducible and economical calibration for particle counting instruments
The RAS 3000 contains an integrated aerosol generator for the generation of a temporally very stable polydisperse aerosol with Cn,max = 35 P/cm³ = 35 x 106 P/m³. At these concentrations the OPCs can be calibrated without aerosol dilution. With the reference particle measurement device (RPM) the variances in number concentration are determined and recorded at all six aerosol outlets. Then, up to five OPCs can be connected to the RAS 3000 at the same time and the number concentrations can be measured. Each of the measured number concentrations at the respective outlet cylinder (AAZ1-6) is finally corrected with the previously determined values with the RPM.
By its nature of being a relative calibration, this calibration method is only dependent on the stability of the used components like the aerosol generator, the aerosol distribution system and of course the reference particle measurement device. The RAS 3000 provides defined, fast, reproducible and economical calibration for particle counting instruments. With this system the users of OPCs can check the work of calibration service providers. Another field of application of the RAS 3000 is the determination of the protection degree of operation rooms according to SWKI 99-3.
New: Test rig MFP Nano plus
Two years ago the version MFP 1000 HEPA for the determination of the fractional efficiency of HEPA filter media according to EN 1822-3 in the size range of 120 nm to 40 μm with the aerosol spectrometer system welas® digital has been presented and successfully introduced into the international market. With the development of the U-SMPS system (measuring particles in the size range of 5 nm up to 1 μm), a new high-performance measuring system is now available, integrated into the MFP.
The new MFP Nano plus with the integrated U-SMPS can test filter media with salt aerosols as well as with oil droplets, e.g. DEHS. By choosing the adequate solution concentration in the aerosol generator the mean generated particle size is precisely defined. Thus, the system can be matched to an optimum counting statistic for the particular MPPS range (Most Penetrating Particle Size). The polydisperse test aerosol is classified with the DEMC (Differential Electrical Mobility Classifier), so that only monodisperse particles of a particular size can get on the filter media for the determination of the efficiency. This procedure minimizes loading effects caused by
the test aerosol on the filter medium at the downstream measurement.
The new Palas® condensation particle counter UF-CPC 50 then determines fast and reliably the appropriate particle number concentration to each particle size. The UF-CPC 50 uses a large optical measurement volume and is therefore optimized for highest counting rates in very low aerosol concentrations.The very high particle concentration in upstream is reduced for the measurement by welldefined dilution systems. The integrated dilution cascades enable dilution factors of 10, 100, 1000 and 10000. For the simple switching between upstream and downstream measurement an automatic upstream/downstream switch is provided.
The cleaning effort at the dilution cascades is minimized by using two simple moveable dilution cascades, one for salt aerosols and one for DEHS. This leads to a fast, economic and defined determination of the filter efficiency according to EN 1822-3.
The series MFP for the evaluation of the dust holding capacity, the pressure loss and the efficiency of filter media has been proven to the entire satisfaction of our customers for years. The entire spectrum in air filter media testing, starting at very low efficient open media up to ULPA qualities, can be carried out with the different versions of the MFP series.
Merry Christmas and a Happy New Year!
(Henry Ford)
Together with you, we went through this year full of new
realizations and experiences. Thanks to your loyalty to us we could continue our successful growth course also in 2011: Thus, we employed three new colleagues and acquired three new sales partners. Furthermore we introduced new products onto the market, e.g. the calibration system RAS 3000 and the universal scanning mobility particle sizer U-SMPS . Our Aerosol Technology Seminar, which established itself as a competent forum for all specialists from industry and research, celebrated its successful 25th anniversary.To give is a tradition just belonging to Christmas. Therefore we give you today our cordial thanks for the positive cooperation and your confidence in our company.
With this year’s Christmas donation to the association „Humanitäre Botschaft – Eine Stadt bringt was ins Rollen e.V.“ (“Humanitarian Message – One City Gets The Ball Rolling”) we give – also in the name of our business partners – handicapped people a little joy. This association realizes projects for the promotion of the integration and mobility as well as for the improvement of the quality of life of handicapped people.
We wish you and your family happy Christmas holidays, health, personal and commercial success.
We look forward to continue working together with you on interesting business opportunities also in 2012.
Merry Christmas and a Happy New Year!
The Palas® Team
Aerosol Technologie Seminar feiert 25-jähriges Jubiläum!
Das erste Palas® Aerosol Technologie Seminar, das den Auftakt zu einer erfolgreichen Seminarreihe bildete, fand 1987 im Hotel Ramada Renaissance in Karlsruhe statt.
Techniken zur Erzeugung, Handhabung, Messung und Abscheidung gasgetragener Partikel gewannen damals in den verschiedensten Bereichen (Luftreinhaltung, Reinraumtechnik, Keramikherstellung, Filtertechnik, Abgasreinigung) immer mehr an Bedeutung. Viele Anwender mussten sich in ein für sie völlig neues und fremdes Wissensgebiet einarbeiten. Andere wünschten einen stetigen Erfahrungsaustausch auf diesem Gebiet.
Mit dem Aerosol Technologie Seminar kamen wir diesen Erfordernissen entgegen und boten ein Forum der intensiven Wissensvermittlung und des lebhaften Erfahrungsaustausches.
Anerkannte Fachleute aus Universitäten, Forschungsinstituten und Industrieunternehmen als Referenten (wie z. B. Prof. Dr.-Ing. F. Löffler, Dr. W. Holländer, Dr. J. Gebhart, Dr.-Ing. H. Umhauer) lieferten in ihren Vorträgen zum damaligen Seminarthema „Praxisorientierte Überprüfung von Faserfiltern“ fundierte und aktuelle Informationen aus erster Hand.
Heute, 25 erfolgreiche Jahre später, ist das Palas® Aerosol Technologie Seminar als kompetentes Forum zur Erörterung und Diskussion der brandheißen Themen für alle Fachleute aus Industrie und Forschung, die sich mit dem Erzeugen und Messen von Aerosolen beschäftigen, längst zur Tradition geworden.
Das Seminar feierte sein 25. Jubiläum am 12. und 13. September 2011 im Schlosshotel Karlsruhe.
Spezialisten ihres Fachgebiets präsentierten als Referenten ihre neuesten Erkenntnisse und Ergebnisse zu den folgenden aktuellen Themen: Nanopartikelmessung, Feinstaub- und Umweltmesstechnik, Kalibrieren von Partikelmessgeräten, Bioaerosole, Filterprüfung, neue Normen.
Neben dem Seminar selbst boten sowohl das schöne Ambiente im Veranstaltungshotel als auch das festliche Abendprogramm Gelegenheit zum anregenden Austausch zwischen Wissenschaft und Praxis.
Während den Pausen hatten die Seminarteilnehmer außerdem die Möglichkeit, sich im Rahmen einer Geräteausstellung über die Palas® Neuentwicklungen zu informieren.
Anlässlich des 25. Seminarjubiläums wurden im Rahmen des Abendprogramms unter anderem Herr Prof. Dr. Christoph Helsper für 25 Jahre Moderation und Herr Dipl.-Ing. Manfred Sauer-Kunze als der treueste Referent jeweils mit einer Urkunde und einem Geschenk geehrt. Auch Palas® Geschäftsführer, Herr Dipl.-Ing. Leander Mölter, bekam eine Ehrung als besondere Anerkennung für 25 Jahre erfolgreiche Ausrichtung des Aerosol Technologie Seminars.
Eine Firmenführung mit praktischen Vorführungen zur Filterprüfung, Aerosolerzeugung und Kalibrierung rundete das Jubiläumsseminar ab.
Teilnehmerstimmen zum 25. Palas® ATS:
- „Besonders gut: Referenten mit exzellentem Fachwissen.“
- „Besonders gut hat mir das breite Themenspektrum des Programms und die – wie immer – äußerst angenehme Atmosphäre der Veranstaltung gefallen.“
- „Aus meiner Sicht war das Seminar eine rundum gelungene Veranstaltung. Besonders interessant war das breite Spektrum der Vorträge, die neue Ideen in die eigene Tätigkeit einfließen lassen werden.“
Ein ausführlicher Bericht über das 25. Palas® ATS ist außerdem auch in der Zeitschrift F&S Filtrieren und Separieren (Jahrgang 25 (2011), Ausgabe Nr. 5) erschienen. Der vollständige Artikel über das Jubiläums-ATS steht Ihnen hier zum Download zur Verfügung:
Meet Palas at the Powtech in Nuremberg!
You are kindly invited to visit us at our booth 6-109 in hall 6 and convince yourself on site of the quality and performance of our new products in the range of filter testing and particle measurement technology:
MFP HEPA/ULPA: media test rig for HEPA/ULPA filters
Fidas® mobile: portable and robust device for the simultaneous and continuous measurement of PM1, PM2.5, PM4 und PM10
Promo® aerosol spectrometer: with aerosol sensors from -120°C up to 470°C!
welas® digital aerosol spectrometer: modular system with time resolution of 10 ms
Charme®: high quality reference aerosol electrometer
U-SMPS: nanoparticle size distributions in the range from 5 nm to 1 µm
RAS 3000: Reference Aerosol Distribution System for validation measurements and the determination of the protection degree of operation rooms
We are looking forward to meeting you!