Q wrote: "The Center for Disease Control says a positive pressure suit is needed. Ebola virus is Biosafety Level 4.
Positive pressure personnel suit (PPPS) with a segregated air supply is mandatory."

The CDC publishes guidelines for facilities. The suits should be worn when treating Ebola patients, period. Not "in case it's airborne". It's not airborne. The CDC guidelines are for hospitals in the US. I don't think the CDC actually has facilities for threating patients, so wouldn't use it "at the CDC" at all.