Interlaboratory Trial for validation of ISO 15923-1: - NAW

ISO 15923-1 Interlaboratory trial information for participants page 1 /3
Document ISO/TC 147 N 747
Document ISO/TC 147/SC 2 N 1281
Document ISO/TC 147/SC 2/WG 63 N 10
Date: 2012-07-31
INFORMATION
for participation in the
Interlaboratory Trial for validation of ISO 15923-1:
Water quality — Determination of selected parameters by a discrete analysis system
— Part 1: Ammonium, nitrate, nitrite, chloride, orthophosphate, sulfate and silicate
with photometric detection
Dear colleagues,
Thank you very much for your kind interest to participate in the interlaboratory trial for the
validation of the new ISO standard ISO 15923-1. Today we would like to give you some
further information on the design and the timetable of the trial which will be carried out in
January/February 2013.
We would like to clarify that our trial is a validation exercise and not a proficiency testing
trial. Therefore, it is crucial that you adhere to the procedure described in
ISO/DIS 15923-1.
Please find in the following table some further technical information for your kind attention
and consideration when preparing your measurements.
Item
Information
Number of expected
participants:
more than 20
Relevant document: ISO/DIS 15923-1
Water quality — Determination of selected parameters by a discrete
analysis system — Part 1: Ammonium, nitrate, nitrite, chloride,
orthophosphate, sulfate and silicate by photometric detection
Dispatch of samples: October/November 2012
Deadline for submission
of results:
Participation fee:
2013-01-31 (deadline)
Free of charge
Matrices: Sample A: Drinking water (Public Water Supply of Muelheim)
Preservation:
Sample B: Filtered surface water (no digestion necessary)
(River Ruhr, near Muelheim)
Sample C:
Sample D:
Municipal Wastewater
Eluate
Refrigeration of samples after arrival to 1 – 5 °C.

ISO 15923-1 Interlaboratory trial information for participants page 2 /3
Item
Information
Reporting of results:
Parameters to be
determined:
Replicates
Filtration:
An electronic record sheet (EXCEL file) will be sent out by e-mail to all
participants. All results shall be recorded in this file.
Sheet: Sample A (DW) = results for the drinking water sample
Sheet: Sample B (SW) = results for the surface water sample
Sheet: Sample C (WW) = results for the wastewater sample
Sheet: Sample D (EL) = results for the eluate sample
The file shall be e-mailed to the organizer. In addition to that the results
shall be printed out, signed and sent back to the organizer by postal mail.
Finally, participants are requested to give some “General Information”
about the measurements. In some cases a choice between pre-set
options will be offered by tick-boxes.
Ammonium, chloride, nitrate, nitrite, orthophosphate, silicate and sulfate
The measurement of all parameters is recommended but not obligatory
for participation.
Please write in the column "Wavelength [nm]" of the record sheet if
you don't take part for a certain parameter
Four independent replicates (analysed in different batches) per
parameter are required
Filtration of all samples through a 0,45 μm membrane filter is
recommended according to Clause 4 of the standard
Concentration range(s): Sample A: Close to LOQ or the natural level in a typical drinking
water, spiking only if necessary)
Performance criteria:
Sample B: in a typical range for surface water
(spiking only if necessary)
Sample C: in a typical range for municipal wastewater
(spiking only if necessary)
Sample D:
Evaluation: According to ISO 5725-2
Report/certificate:
in a typical range for eluates
(spiking only if necessary)
Limits of Quantification (LOQ) determined according to common
definitions should be reported to have an idea on the mean performance
of the method
(see data sheets, delivered with the samples)
The results of the trial will be reported in detail to all participants in an
anonymous form. The participants can identify their own data via the
laboratory code. Detailed tables and graphs will be delivered (mail with
pdf files).
Date of delivery of the
results to WG 63:
A signed certificate with the results of the lab will be forwarded by postal
mail.
April 2013

ISO 15923-1 Interlaboratory trial information for participants page 3 /3
Contact details of the Interlab organiser:
ULRICH BORCHERS
c/o IWW Water Centre
Department Water Quality
Moritzstrasse 26
D – 45476 Muelheim an der Ruhr
GERMANY
Phone: +49 208 40303 210
Fax: +49 208 40303-80
e-mail: u.borchers@iww-online.de
Finally, we would like to express our warm thanks on behalf of the convenor and the
members of the WG 63 “Discrete analysis” for your kind willingness to help us to validate
ISO 15923-1.
We wish you good success!
In the case of any questions, please don’t hesitate to contact us by e-mail or phone.
Best regards
Simon Gillespie and Ulrich Borchers