FS-ONE MAX installed and cured. Effects due to exposure to standing water?

Hello Luke,

FS-ONE MAX has an ASTM G-21 of Class 0 which means it remained free of fungal growth after exposure to a high humidity environment for 28 days (I've attached documents below for you). We also have systems with FS-ONE MAX that have W-ratings which have been tested under specific firestop and assembly conditions with 3-ft head of water for 72 hours with no leakage. For more information on W-ratings see:
https://ask.hilti.com/article/what-is-a-w-rating/7jrjna

Though FS-ONE MAX has passed these tests standards and is able to achieve the certifications and ratings involving water/moisture, it is not recommended to have the sealant exposed for excessively prolonged periods of time.

Regards,
Michael Vu
Fire Protection Design Team