The standard ISO DIS 8655 describes both the design and the testing of the bottle-top dispenser. The following Testing Instructions describe how to apply the ISO standard in practice.
We recommend a testing every 3-12 months. This interval may be adjusted to individual requirements. For example, when working very frequently or when using aggressive media, the instrument should be tested more frequently.
These Instructions may also be used as a basis for the supervision of testing devices to DIN EN ISO 9001, DIN EN ISO 10 012 and DIN EN ISO/IEC 17 025.
For the regular examinations required by DIN EN ISO 9001, DIN EN ISO 10 012, DIN EN ISO/IEC 17 025 and the GLP Guidelines, BRAND® additionally provides a calibration service. Your instrument will be returned within a few days together with a test report. For more detailed information, please contact your labware supplier.
If there is a malfunction of the instrument (e.g., piston difficult to move, sticking valves or leakage) please consult the "Troubleshooting" section of the operating manual.
Through the use of calibrated testing devices (balance and thermometer), the requirement of DIN EN ISO 9001, DIN EN ISO 10012 and DIN EN ISO/IEC 17025 to refer the test to the national standard is fulfilled. The calibration of the balance e.g. can be carried out either by DAkkS calibration or official certification of the balance, or by calibrating the balance with appropiate weights that are traced to the national standard. The calibration of the thermometer can also be carried out by DAkkS calibration or official certification, or by a comparison with thermometers that are traced to the national standard (under defined conditions).
The values obtained by weighing during the gravimetric test are only the mass values of dispensed volume without correction of air buoyancy. In order to obtain the actual volume, an adjustment calculation to account for water density and air buoyancy must be carried out. To facilitate your calculations and evaluations, we recommend the use of the Windows-compatible calibration software EASYCAL™ from BRAND®.
(Example for ten weighing values)
⇒ For factor Z (Table 4)
⇒ Enter value into Test Record (6a).
⇒ For factor Z, Table 4
⇒ Enter value into Test Record (6b)
⇒ Enter value into Test Record (6c)
⇒ Enter value into Test Record (6d)
Use the error limits per Table 5 and 6, or define your own error limits. ⇒ Enter values into Test Record (6e, f).
If calculated values A [%] and CV [%] are smaller than or equal to the error limits, the instrument is in good working order.
If the calculated values are larger than the error limits:
If these measures are not successful, we offer you the possibility to have your instruments calibrated by the BRAND® Calibration Service.
Error limits for Dispensette®
10 single measurements per test volume according to DIN EN ISO 8655. For definition of A, CV and s see sample calculation chapter 5. For checking of partial volumes the values for A [%] and CV [%] which are related to the nominal volume have to be converted.
For calibration, the error limits to be observed by the operator must be individually defined by the user. For this purpose, the following methods can be applied:
The above procedures fulfil the requirements of DIN EN ISO 9001, DIN EN ISO 10012 and DIN EN ISO/IEC 17025.
BRAND® offers a full service including calibration and adjustment of Brand- and foreign instruments as well as maintenance and repair if necessary - only for BRAND®- instruments. This saves money and adds the benefit of an independent review organisation for the calibration of the instruments. Further information and the order form for repair- and calibration service are found on www.brand.de.
At BRAND®, a team of qualified staff, working in temperature and humidity controlled rooms using the most modern balances and calibration software, calibrates Liquid Handling instruments, regardless of their make, according to DIN EN ISO 8655.
Instruments with adjustable volumes such as HandyStep® electronic, Transferpette®, Transferpette® S, Transferpette® electronic, Transferpette®S -8/-12, Transferpette® S -8/-12. Transferpettor or Dispensette®, Digital Burette or Titrette® are tested at nominal volume, and at 50%, 10% or 20% of nominal volume.
To document the results, a detailed test report is compiled.
EASYCAL™ simplifies the tedious task of calibrating liquid handling instruments and glass or plastic volumetric instruments to DIN EN ISO 9001, DIN EN ISO 10012, DIN EN ISO/IEC 17025 and GLP standards. The procedures are outlined step-by-step, and all calculations are performed automatically. Reports are generated to document the calibration. All you need is an analytical balance, a PC Windows® 98/2000, NT (SP6), XP, Vista, 7, printer (optional) and EASYCAL™ software.
The calibration certificate contains all important test data on one page.
The German Calibration Service (DKD) was founded in 1977 as a joint task of state and economy and constitutes the link between the measuring equipment in industrial and research laboratories, testing institutions and authorities and the national standards of the PTB (the German Institute of Physics and Metrology). It effectively supplements the existing verification system which serves above all the purposes of consumer protection. Based on the legal requirements the DKD Accreditation was successively transformed to the DAkkS Accreditation (Deutsche Akkreditierungsstelle GmbH), starting from 2010. BRAND® has been accredited by the DAkkS since Apr. 23, 2013, with the certificate number D-K-18572-01-00.
The DAkkS-Calibration Certificate documents officially on a high level the traceability of measuring results to national and international standards and to international SI-units, as required by standards as DIN EN ISO 9001 and DIN EN ISO/IEC 17025 for monitoring of measuring devices.
DAkkS-Calibration Certificates are issued when calibrations of an accredited laboratory are requested, when high level calibrations are necessary, when national and international standards are demanded and when reference instruments have to be calibrated.
DAkkS is a member of the International Laboratory Accreditation Cooperation (ILAC), the highest level international institution for laboratory calibration, and is a signatory to the MRA – Mutual Recognition Agreements.
The accreditation bodies that are signatories to the ILAC mutual recognition agreements (MRAs) recognize their mutual equivalence, and the equivalence of the calibration certificates issued by those same signatories. Likewise, signatories are obliged generally to promote and recommend recognition of the calibration certificates of other signatories (excluding factory calibration certificates).
The DAkkS is a member of the EA (European Co-operation for Accreditation), which again is a member of the ILAC (International Laboratory Accreditation Cooperation). A multilateral agreement assures obligatory recognition of the DakkS calibration certificate in a variety of countries.
In 1998 a calibration laboratory for volumetric instruments at BRAND® has been accredited by the German Calibration Service according to DIN EN ISO/ IEC 17 025. Our calibration laboratory is therefore authorized to issue DAkkS-Calibration Certificates (in several languages) for the volumetric instruments listed below. Furthermore we offer adjustment and – for BRAND® Liquid Handling instruments – repair and maintenance.
For ordering information on DAkkS-Calibration Certificates for volumetric instruments please consult our General Catalog.
BRAND® calibrates the following volumetric instruments (new or already in use and regardless of their make):