Yea, I'd recommend an N95 mask (or cartridge filter if you have it) for ANY type of sanding/polishing. There's all kinds of harmful stuff in almost anything. For example any type of treated wood before 2003, or around there, is treated with arsenic. So if you have a 10+ year old deck that needs sanding and refinishing, then you are setting yourself up to inhale a good amount of Arsenic. Its treated with copper now.
The mask captures the particulate. Use a fan to move anything that's vaporous away from you as that will go through the N95.