Release Notes

S-Risk 1.3.1

S-Risk 1.3.1 adds 2 new substances to the list of default chemicals in the Flemish version of S-Risk: 

  • perfluorooctane sulfonic acid (PFOS)
  • perfluorooctanoic acid (PFOA)

The substance information sheets for these new compounds can be found here.  A detailed report discussing the derivation of soil remediation values (SRV) can be found here.

Both of these documents are also available from our Documents page.

Contact us via if you have further questions!

S-Risk 1.3

S-Risk 1.3 is a release with significant changes in parameters for the S-Risk model, and some platform optimizations.

The changes mainly concern:

  • changes to soil ingestion parameters, switching to P60 values instead of P95 
  • changes to risk parameters for chlorinated compounds: dichloromethane, tetrachloromethane, trichloroethene, 1,1,1-trichloroethane and tetrachloroethene
  • bug fix which causes PDF report generation to fail in some situations

A detailed note describing the parameter changes can be found here.

Full details concerning the review of risk parameters for the chlorinated compounds can be found in this report, also available from our Documents page.

Contact us via if you have further questions!

S-Risk 1.2.6

S-Risk 1.2.6 is a minor bugfix release

  • Fix for an issue where evaporation to outdoor air was not consistently calculated for elemental mercury and methyl mercury. 

  • Fix for an issue where the calculated concentration in eggs was not shown in the "detail results" section of the PDF report.

Contact us via if you have further questions!

S-Risk 1.2.5

This release includes a number of fixes and some maintenance and parameter adjustments.

General fixes & changes

  • Fix for incorrect water-filled porosity in the capillary zone (θwcz):

    By default, θwcz amounts to 0.34 (FL/BRX) or 0.391 (WAL) for the "generic" soil layer type. However, for a newly created simulation – which has one “generic” standard soil layer by default – this parameter was systematically set to 0 instead of the correct default value. For all other simulations, i.e., simulations where the default “generic” soil layer has been replaced by (an)other soil layer(s), the correct (default) value for θwcz is set. Also, in simulations where a second/third/… generic soil layer has been added, the correct (default) value for θwcz will be taken.

    We have discussed this issue with the FL, BRX and WAL government. In case the involved simulation(s) is (are) resulting from a closed file, you don't have to do anything. In other cases, i.e., when you want to make re-use of an involved simulation (created before release 1.2.5), either for creating a new simulation (by using the copy function) or for doing new calculations with the respective simulation, you manually have to adjust this parameter value. How can you do this?

  • Switch to Tier 2 mode and go to the “Soil” tab;
  • Select the generic soil layer, click on the “Customize” button and modify the soil layer name;
  • Behind "θwcz (m³/m³)", enter 0.34 (FL/BRX) or 0.391 (WAL) instead of 0.

    Contact us via if you have further questions!

  • Changed thousands separator for numbers to space, to avoid confusion with decimal numbers. 
  • Adjustments to summary report, so it will be saved correctly to PDF in Chrome.

Parameter adjustments

The Walloon government decided to change the toxicological threshold values of some default WAL chlorinated substances:

  • for hexachlorobenzene, the values for systemic threshold effects have been changed:
    • oral TDI and dermal TDU: 5.0E-5 mg/kg bw/d;
    • TCA: 2.45E-4 mg/m³;
  • for pentachlorobenzene, the TCA value for systemic threshold effects has been changed: 2.8E-3 mg/m³;
  • for 2,3,4,6 tetrachlorophenol, the TCA value for systemic threshold effects has been changed: 0.35 mg/m³.

Please, be careful when making re-use of simulations (created before release 1.2.5) containing these substances, either for creating a new simulation (by using the copy function) or for doing new calculations with the respective simulation! In both cases, you manually have to adjust this parameter value. How can you do this?

  • Switch to Tier 2 mode and go to the “Chemical” tab;
  • Select the appropriate chemical, click on the “Customize” button and modify the chemical name;
  • Go to the “Risk” tab and select the respective chemical;
  • Within the “Threshold effects – Systemic effects” panel, enter three times the appropriate value for TDI, TDU and/or TCA.

Contact us via if you have further questions!

S-Risk 1.2.4

S-Risk 1.2.4 is an interim release containing a minor fix and some improvements to the web application.

  • fix for handling of Kd factors in situations with a separate infoor profile, for metals without a Kd formula
    Users with simulations that were possibly affected by this, have been informed by email.
  • several fixes to optimize network traffic to the server

S-Risk 1.2.3

This version is a minor update with reporting improvements and fixes for some specific operational issues.

  • exposure routes are now more clearly labeled in the summary report
  • additional link is available to the summary report, in case it doesn't auto-appear after calculation
  • fix for counting the number of simulations being processed
  • minor improvements in the summary report
  • exposure routes are now shown in the same order everywhere in the reports

S-Risk 1.2.2

This release includes a number of maintenance adjustments and minor fixes, and further paves the way for the introduction of the Walloon edition of S-Risk. 

General fixes & changes

  • several improvements in the summary report
  • improvements in the archived simulations interface
  • improved consistency of toxicological endpoint ordering in Risk tab & detailed reports
  • improved error reporting in web interface
  • fixed missing translations in Dutch interface
  • improved error reporting in case of groundwater table regarding concrete slab depth
  • fix for decimal separator in scientific notation
  • improved handling of "stuck" simulations that seem to keep running forever
  • better transaction handling in the database to optimize performance

Parameter adjustments

These changes can affect the results of some Flemish/Brussels S-Risk simulations. 

All existing simulations in our database have been reviewed, and the S-Risk accounts with simulations possibly affected by these changes will be notified by email. Contact us via if you have further questions!

  • fixed handling of parameter "Fraction of soil in indoor dust": sometimes, a wrong value was assigned when changing applications for a simulation;
  • for 1,2,3-Trimethylbenzene and 1,2,4-Trimethylbenzene, the dermal TDU value for systemic threshold effects has been changed. Old value: 0.15, new value: 0.05.

S-Risk 1.2.1

This release is the first public release in the 1.2 series. It introduces a new, much-requested archiving feature, and a range of backend changes to enable the use of S-Risk in the Walloon region. During this process, a considerable number of generic S-Risk issues were fixed and improved, too.

New features

  • added "Archiving" functionality for the simulation overview: simulations not consulted during the last two years, will be archived automatically; other unneeded simulations can be moved manually out of the way

Introduction of S-Risk Wallonia

  • parameter database is extended to cover Walloon-specific studies - available in Walloon S-Risk accounts. This includes additional chemicals, soil layers, land uses and fine-tuning of default parameter values to the Walloon legislative and environmental context.
  • extended account functionality to cover Walloon accounts next to Flanders/Brussels accounts
  • interface adjustments to indicate the S-Risk region associated with the logged in account
  • introduced read-only accounts for transitioning customers
  • revised of the licensing agreement and registration system to cope with the new cross-regional context

General fixes & changes

  • further structural changes to the database to improve performance and responsiveness 
  • backend improvements for database consistency and robustness of parameter defaults
  • fine-tuning of the optimization algorithm to ensure results in a wider range of concentrations
  • fine-tuning of the comment requirements when changing parameters
  • minor corrections and adjustments in parameter database:
    • "total time on site" parameter corrected for some scenarios - without influence on the results
    • default value for ABS_dermal for blank chemicals is changed to 0.25
    • corrected the CAS numbers for Zinc, Arsenic and Trichloroethene
  • improved validation of parameters in Chemical & Risk tabs and related in-browser error reporting
  • fixed some issues in the Graph tab
  • functionality improvements in Risk tab, to improve consistency of risk parameters
  • fixed issues with display of soil/dust ingestion values in Scenario tab
  • fixed issue where Water tab - water consumption factors were uneditable in some cases
  • fixes, improvements and adjustments to the reports, both the summary report and the extended PDF report

The manuals will soon be adjusted to reflect these new features.


S-Risk 1.1.5

Released on June 30, 2016.

List of changes in this release

S-Risk 1.1.5 introduces the new optimization backend for applications 1 and 3, and a number of smaller fixes in the user interface.

The new optimization algorithm is a major improvement for the calculation of critical concentrations. It is better at finding the relevant critical concentrations, more capable of dealing with nontrivial RI functions and runs significantly faster than the old algorithm.

Full list of changes in this release:

  • complete overhaul of optimization backend - applications I & III are faster and more robust
  • optimization error messages and remarks have been formulated to be clearer and more user-friendly, both for the older optimization algorithm as well as the new one
  • optimization error messages and comments are now shown in the summary report, too
  • default application type for new simulations is now application II
  • numbers reported in the "exposure overview" in the in-browser report are now consistent with the extended PDF report
  • better tuning of CI & RI calculations and critical concentrations in function of enabled exposure routes
  • improved handling of route enabling/disabling: dermal exposure via water and inhalation via bathroom air are now systematically coupled
  • reports on optimization results will show warnings for metals based on non-standard models, and suggest to double check with the Graph tab
  • renamed region "Flanders" to "Flanders/Brussels", as the model and parameterization is valid for both regions
  • region indication is now prominently visible in the application page header
  • fixed situations where the summary report wouldn't show up after model calculations
  • entering 0 for soil pH, organic matter or clay percentage will raise an error message now
  • the extended & printed summary report now also include the simulation label
  • lots of smaller fixes for text labels in the user interface and reports


Released on February 2nd, 2016.

List of changes in this release

S-Risk release is a bugfix release, fixing a problem introduced with the previous 1.1.4 release.
In 1.1.4, adjustments were made to make the outdoor air model more consistent with user-provided soil air measurements (see item 2 in Model adjustments in the 1.1.4 release notes). These adjustments introduced a new problem concerning volatilization from groundwater to outdoor air, of importance to simulations where groundwater contamination is determining outdoor air concentrations and outdoor air is determining for the global risks.