How we did it ...
To measure the UV protection we used a UV radiation detector.
We turned the reader on, we placed the sensor in the direction of the sun.
We put the control in front of the reader first. This made sure the test was fair.
The we went through all 8 sunscreens.
Returning to the control in between each one.
We wrote down three readings for each and calculated an average.
La roche posay spf50
This sunscreen is efficient against UV radiation, even when it passes 400 nm. It is probably the best suncream we tested.