One of the reasons face masks were a common sight in Japan even before the Covid-19 pandemic was the formidable hay fever that overwhelms about 40% of the population at certain times of the year. The problem is that plain masks are often not enough to fight the 20-30 µm pollen particles and this is why if you are serious about your pollen allergy, you should seriously consider something like the Thanko Pollen Blocker 3.
Simple enough that it doesn't even need a switch (to switch it on, just plug it into your own USB battery), the Thanko Pollen Blocker 3 covers your whole head and uses two powerful fans to circulate the air inside its hood. With a large visor that allows full visibility, a filter that handles anything from 10 µm, and with a securing cord to make it almost airtight, it means you can do pretty much anything in and out of the house without worrying about allergies or contamination!
The Thanko Pollen Blocker 3 features: