If they weren't doing this in a suburb I'd say 'Congrats'-- but to knowingly be generating x-rays in a residential neighborhood is really, really selfish and disrespectful to neighbors.
Looking at the video linked elsewhere, this was run in a bedroom on the second or even third floor of a single-family residence. He mentions not being able to detect x-rays more than 35ft from the device. I think a neighbor would have to be trying to get in range to be affected.
Here's the video again, queued up to the view out the bedroom window: https://youtu.be/92M5qcjDkaU?t=1m5s
What's lethal at 3 inches probably isn't measurable at 50 feet.
Still, I think if it had been me I'd have some lead shielding around it.