Surviving 'sand storms' with potential suffocation effects

[Xaratherus]

At some point in the near future I'll be playing in a slightly modified Slumbering Tsar campaign. The DM has warned us about a potential danger ahead of time because: First, we will be warned about it IC before the adventure begins; and two, without proper preparation it would basically lead to a TPK.

Unfortunately, to really get advice I have to give some detail, so please read and offer advice only if you won't likely be playing in this campaign
at some future point (or, well, if you don't care and can avoid metagaming):

Spoiler:

In the game, while out in the desert there will be periodic dust storms filled with fine bone particles. The storm itself can do ongoing damage ('minor' according to the DM), but the real risk is that anyone failing a Fort save gets a mouth- and nose-ful of the particles and begins to suffocate. You can rinse them away with water, but not until after the storm - which lasts a minimum of 10 minutes - abates.

With that in mind, what sorts of spells\mundane items\magical items could people suggest to avoid a painful, suffocating death?

[Nitro-13]

Im gonna say a bandana or some other sort of fine cloth covering should give a small bonus to the save, but thats up to your gm.

[Xaratherus]

We're probably going to look into the Filter Hood, which he's already said will grant us the +2 to our saves versus the effect.

Thus far I haven't found any magical items we can really afford at our level (7th) that would immediately help. I suppose since we'll have a caster that a wand of Resilient Sphere might do it?

[Joanna Swiftblade]

Taking the spell Web Shelter would do the trick, and it's only a level 2 spell that shows up on every spell list except inquisitor, magus, and paladin. Mundane wise, goggles on the eyes to stop blindness, a wet cloth over the mouth and nose does the trick (in a pinch you could just pee on a rag, if it worked against chlorine gas attacks in WW1, it will work against some pesky sand). I'd suggest the former if you can afford to wait it out, but in case you run out of spells or just get caught at a bad time, the having a back up is always good.

[H.P. Makelovecraft]

A large tarp that you can throw ofer yourself and crouch down, I'd its only 10 minutes that won't be enough time to bury you alive..I think?

[Xaratherus]

Web Shelter probably would not work as a solution; the event deals some amount of damage each round, and I'd guess that's probably to physical objects also; the webbing probably wouldn't survive it.

Tiny Hut would be a valid option, but the wand is a bit pricey; scrolls might be more viable. I know Rope Trick won't work, because the DM told us as much.

A simple tarp could possibly work; I'll check with the DM. Thanks for all the input so far!