It's a very manageable risk (i.e. this isn't like dredging a canal with a nuclear bomb), but high power electromagnetic radiation can hurt you. Not in the 5G-causes-arse-cancer sense, but you could end up at least microwaving some birds.
Maybe not the test, but current high powered microwave transmitters aren't safe to stand in front of. And I assume the production product would be higher power than those.
