Question: when using particle acceleraotors how do you protect yourself since x-rays are very dangerous as they can see throught your skin hence we are allowed so many x-rays a year?

Joshaniel Cooper answered on 12 Nov 2014:

Good question, we do indeed have to protect ourselves from the radiation. X-rays can’t easily go through lead, but lead is actually very expensive, so we use small amounts of lead and huge blocks of concrete to put around the x-ray beam so we are safe outside it. Each of the concrete blocks can weigh up to 50 tonnes and we have thousands of them, but even so we have people who go around with a radiation detector (Geiger counter) to check that none of the radiation is escaping through the gaps between them.