Its a safe move. I am not sure what kind of paint is used in your area but some can have harmful fumes that are detrimental to orchids - similar to tobacco smoke exposure.
I have also seen quite a few horror posts about paint spilling on orchids and some to the point of total loss.
*A contractor actually painted [compressed sprayer] someone's outside wall without relocating the vandas that were hanging on poles about 2 feet away from the wall. The result is that the sides of the vandas facing the wall are now colored mocha.