Inogen at Home vs. coffee

Hi,

My mom's Inogen at Home unit caught a small amount of splash, when she spilled a coffee the other day. I cleaned the particle filter, and that's ok. I can see that some there are some splashes on the columns.

There are no error codes and the output volume is on target (per Liter Meter measurement). I don't know if O2 purity is affected though. Although it was purchased more than a year ago, Mom has only been using the unit steadily for a couple months.

Can I wipe the outside of the metal columns with a damp cloth?

Thank you, Misty