Just remember to purchase a decontamination unit so you won't have to breathe any of whatever dust/particles you've covered your clothing and boots with while wearing your mask
Screwfix do some reasonable priced disposable ie rated for a work period which is normally 8 hours personal I get FFP3 rated ones but the choice is yours depending on where you're going and how much you value your life lol
But as above if it's all over your clothing hair etc ?
Probably more issue with mold spores and Pigeon crap TBH and you don't want to develop Pigeon Lung
You're doing the right thing looking into it anyway, I've been messing about in bunkers and stuff since I was about 10 year old unprotected, 11 years down the line my respiritory system seems to be suffering a little from it all... Not much good telling a 10 year old about the dangers of fungus, pigeon shit and azzy though is it...?
He asked for a respirator not a dust mask so I merely answered what was asked lol. I agree with what you say though you would look like a tool and there are more suitable products about.
My thoughts, as a medical man, is that overall the risk is very minimal. Unless you are breaking things up or kicking around a lot of dust then it's unlikely that you will get significant exposure. As for fungus etc, if it smells bad and irritates the upper airway, then just leave asap
Just remember to purchase a decontamination unit so you won't have to breathe any of whatever dust/particles you've covered your clothing and boots with while wearing your mask