BTEX and MTBE
- two proficiency testing items on different concentration levels
- 600 mL per proficiency testing item
- Synthetic samples (IFA): concentration range: 0-25 µg/L
- In round CB13 there is the possibility to order BTEX/MTBE and VHH together at a reduced price.
- The specified standard deviations for proficiency assessment (z-score-criteria in %) and lower limits apply to synthetic samples in the year 2026
and are calculated from interlaboratory comparisons 2015-2025.
The standard deviations are recalculated and updated at regular intervals.
| Parameter |
standard deviation for proficiency assessment
based on the assigned value |
Lower limit |
|---|
| MTBE |
14 % |
0.1 µg/L |
| Benzene |
14 % |
0.5 µg/L |
| Toluene |
13 % |
0.7 µg/L |
| Ethylbenzene |
16 % |
0.5 µg/L |
| Sum of m- and p-Xylene |
18 % |
0.78 µg/L |
| o-Xylene |
15 % |
0.5 µg/L |
| Proficiency testing round |
Registration deadline |
Dispatch |
Organisation |
Proficiency testing item |
Closing date |
| B-CB13 |
05.10.2026 *) |
19.10.2026 |
IFA |
synthetic |
20.11.2026 |
*) Registration after the registration deadline: on request
- Contact IFA:
Caroline Stadlmann, Ing.
Phone: +43(0) 1 47654 97306
The proficiency tests VHH and BTEX/MTBE in real water samples (cooperation partner UBA) will be offered in an alternation mode.
In 2026 VHH are offered and a proficiency test for BTEX/MTBE for real water samples will take place in 2027.