Cleaning the inside of the unit

What is the best tactic to use for cleaning the inside of the drobo unit? I have a Drobopro 8 bay.

One of my drives has failed and I need to replace it with a new. While I’m at it, I might as well clean the inside of the unit as there’s some dust showing on the drives.

Do you use an aerosol “compressed air” canister or do you use a damp/dry cloth (microfiber or not) or a swifter like duster?

What’s your preferred method such that it won’t damage the interior?

Thanks!

I haven’t cleaned one yet (Drobo Gen2 & Drobo 5N), but it seems like the compressed air sounds good as long as the drive is powered off. I’d be a little afraid of wet rags, etc.