A partner reported that they noticed a difference in the instructions we state in the app and what the manufacturer says:
Hach: instructions on the bottle say to dip the test strip for 1 second, wait 30 seconds, then take a reading.
Caddisfly: when the 30 second timer reaches 0, it resets and does another 30 seconds before taking a reading
After some research, we found out that around September 2020 HACH changed the strip test in how testing is done and change in the patch colour. The change in the patch colour possibly means that the Caddisfly app does not ready the test result properly leading to wrong results.
Thus the current implementation is incorrect as the data generated may be wrong what can lead to wrong decisions based on the data. Thus we need to remove this testing method and provide an alternative for our partners to be able to continue their work.
We looked at options:
remove the test and suggest to switch to Quantofix that we support, but as partners might have purchased the HACH strips already, this is not a viable option
remove the test and add a new one for the new strips version - here we have an issue with backwards compatibility. If we remove the test, what happens with existing survey definitions, surveys on the app that are not updated but suddenly cannot test and the Lumen datasets not having the test definition based on which the extract multiple transformations works. --> too risky technically and not feasible as a solution we can quickly roll out
change how the testing is done currently - remove the automatic strip test reading a move to the user taking an image and inputting the two values in manually.
We decided to try the last one as:
existing survey definitions will not be affected
existing data collection can proceed - user only needs to update the Caddisfly app
if tests confirm - the entire data workflow and backwards compatibility should not be an issue
A partner reported that they noticed a difference in the instructions we state in the app and what the manufacturer says:
After some research, we found out that around September 2020 HACH changed the strip test in how testing is done and change in the patch colour. The change in the patch colour possibly means that the Caddisfly app does not ready the test result properly leading to wrong results.
Thus the current implementation is incorrect as the data generated may be wrong what can lead to wrong decisions based on the data. Thus we need to remove this testing method and provide an alternative for our partners to be able to continue their work.
We looked at options:
We decided to try the last one as:
This means we need to: