I've shot at the Oregon coast off and on since the 1980's. The single biggest problem there is airborne sea spray and heavy fog...airborne micro droplets. Being an eyeglass wearer, I have the advantage of being able to gauge, approximately, how badly my lens front might be from spray accumulation: when my eyeglasses are messed up, I know a lens in active use and aimed toward the water direction might be getting similarly messed up, but to a lesser degree since I have a lens hood on at ALL times, so every 2 to 3 eyeglass cleanings, the lens usually needs swabbing. On some days, there is a LOT of low, beach-level spray. On some days, it is higher, above the ocean, and some days it is airborne, 100 or so feet up, at at the bluff level, where highway 101 runs from California to Astoria. Some days spray is a huge issue! it depends a lot on the waves and surf conditions, and the wind direction.
My solution is simple: use a lens hood whenever possible. Keep the lenshood pointed DOWN, at your feet, when not shooting. CLEAN the front of the lens when it gets "enough" seaspray on it to make it worthwhile to clean it. On some days, that might be every 10 minutes, but on days like that, it is very unpleasant to be there. Where I live, blowing sand might, and I mean might, rise six inches to a foot off the ground during gale-force winds or better; things here are just too danged wet for sand to ever blow to where it can reach more than knee-high, so wind-blown sand is a non-issue here.
Lens hood. Lenshood pointed down. Change lenses FAST, and turned away from the wind direction. To wipe the sea spray off, I use white napkins, use them once, then discard. I carry a ziplock bag of them with me, and spares in the car. For "real" cleaning, I have a microfiber cloth, but microfibers are not that good with liquids--tissue/napkin works better, but you need to use a light touch. If you want to plop a UV filter on, you can, sure. Before wiping a lens front or filter make danged sure there is not sand or grit that the wiping cloth or tissue might pick up! Huff some breath on there, and use a light touch, and wipe the seaspray off, toward the edges of the lens. Then go around the edges. Then, put the lens hood back on.
My experience is that sand gets to camera gear MOSTLY not through the air, but almost always through 1) camera bags or backpacks 2)pockets 3)your own clothing, hands, and arms, after having touched sand, hence the big paintbrush. A camera bag that is placed down on the sand is where the sand gets in: lenses and stuff that go IN TO that bag pick up sand while inside the bag.
My BEST TOOL though, at the beach, for sand/grit is a couple of good paintbrushes, one small one, and one 1.5 inch wide actual painting brush, for brushing off sand. For working with people, I carry a bigger paintbrush, a 3" wide-nylon bristle one, which is really good for wiping sand off of people.