International Plant-analytical Exchange - IPE
Proficiency tests
Participation is open to all laboratories.
Test programme | Plant |
Number of rounds | 4 per year |
Number of samples | 4 per round |
Sample size | 20 g |
Origin | Natural source |
Exercise name | IPE |
General Information
- The sample types/matrices are chosen to represent the materials which you normally analyse.
- The plant samples are dried at max. 70°C and milled and sieved to <0.5 mm.
- The homogeneity of each batch of samples is tested on a selection of parameters.
- The dried plant samples are stored at -20°C and are stable over a number of years.
- You analyze the test materials according to your normal validated methods and procedures for those elements and parameters you are interested in.
- Your results are processed at WEPAL-QUASIMEME and published every three months under confidential code names.
- The reports contain all data, statistical evaluation including Z-score plots and method information about the method used.
- Your reports are available within three weeks after the submission deadline.
- New determinands can be added on request.
Determinands and analysis
Major and Trace Elements
Determinand group
- Inorganic Chemical Composition (Nutrients, major and trace elments)
- Real totals (Elements including silicates)
- Acid extractabel inorganic composition (so-called totals) (Elements excluding silicates)
Click here for more detailed information about the determinands and the scope of accreditation.
Nutricional values
Determinand group
- Nutricional values
Click here for more detailed information about the determinand and the scope of accreditation.
Other determinations
Determinand group
- Isotopes
Click here for more detailed information about the determinands and the scope of accreditation.
Exchangeable cations
Determinand group
- Act. CEC using cobaltihexamine (AFNOR NFX 31 130)
- Act. CEC using 0.01M BaCl2 (ISO 11260)
- Act. CEC using 0.1M BaCl2 (UNEP-UN/EC 91065A)
- Pot. CEC using 1M NH4-acetate at pH=7
- Pot. CEC using 1M or 0.1M BaCl2-TEA at pH=8.1 (ISO 13536 OR BZE)
- Pot. CEC using 1M NH4Cl (BZE)
Click here for more detailed information about the determinands and the scope of accreditation.
Others and Experimental
Determinand group
- Other determinations (Moisture content, CN detn, stable isotope ratios, additional extractions)
Click here for more detailed information about the determinand and the scope of accreditation.
Webshop
Samples of previous proficiency tests are sold as reference materials. Available materials can be selected and ordered in our webshop. Participants of our proficiency tests are entitled to a discount.