Ionizing radiation can be electromagnetic (X-rays, gamma rays) or particulate (alpha, beta, neutron). Radiation can occur in laboratory spaces when using radioactive material, X-ray instrumentation, or particle accelerators. Whether using radioactive materials or radiation sources, lab personnel must be trained to do so and pass the courses Machine Produced Radiation Training, and Radiation Safety Training on eNDeavor. After training has been completed, trainees must contact the Radiation Safety Officer, TJ Whittenhall, to schedule hands on training.
The guiding principle when working around ionizing radiation is known as ALARA, meaning: As Low As Reasonably Achievable. Lab personnel should avoid ionizing radiation when it has no direct purpose or benefit and should avoid hanging out next to a radiation source. The ALARA principle can easily be followed by considering Time, Distance, and Shielding. Never spend excess time near a radiation source. Increase the distance between you and the radiation source whenever possible. Use shielding to minimize dose when working with a radiation source.
Shielding differs depending on the type of ionizing radiation. Alpha particles can be shielded by paper or skin. Beta particles are more energetic and require aluminum or thick plastic for shielding. Gamma/X-rays require lead for shielding as they have no mass and are highly penetrating. Neutrons are even more penetrating because they are uncharged and require lead+concrete for shielding.
Additional details can be found on the RMS website and in the radiation safety manual.