There are proper ways to use the decatlhon snorkel masks as respirators as demonstrated by the czech team: Covmask team.
We are in active discussion with peers to fully understand TSI portacount settings, resulting fit scores and interpretation in these times of urgent need. As soon as we have a definite solution this will be shared on this website as soon as possible.
If you would like to be updated about this send us an email at decathlon@antwerpdesignfactory.be.