We’re building a plant health model using the sample chamber and we’re worried that build up of residue may begin to affect results. Ideally we would clean the chamber using an alcohol solution. Is this safe to do?
Yes, that sounds fine.
Note however that in case that the optical sensor is dirty, you should clean it by wiping it gently with a soft, clean, dry cloth. That is because the device itself is not waterproof and should be protected from water and other liquids.