I use this, never used a mask.
https://www.jpost.com/health-science/anti-viral-nasal-spray-effective-against-covid-19-673481
Made-in-Israel anti-viral nasal spray found effective against COVID
Enovid, a spray developed in Canada by SaNOtize and manufactured in Israel has been found to reduce viral loads in confirmed COVID-19 cases by 95% in 24 hours and 99% in 72 hours
Xlear with xylitol is just as effective and you can make it yourself easily.