mvp Your first link says “open air over” which I read as an unsealed motor. Dirt collects in an unsealed motor, which could start a fire as dust heats up in there.
Second link doesn’t SAY sealed motor, it is an indoor fan. Again, venting holes for hot motor lets in dirt, dust that can self-combust to cause a fire. Other fan models lower under the description one with a yellow blade fan SAYS Outdoor fan. Reading its description it says weatherproof, SEALED motor, which means no vent holes to let in dirt or dust.
I would skip the two fans you linked, as unsuitable in a barn environment. Too much dust in the air with hay being fed, bedding dust, breezes blowing thru carrying dirt and dust. You WANT a sealed motor fan in the barn! You can buy fans from those brand names, but pick a model with a sealed motor in the description as a SAFER fan choice for your barn. Farm-Tec also sells fans for “wet and dirty” environments that have sealed motors for safety, as a third shopping option.