I am looking to do some experimentation with x-ray imaging of non-living materials, and need advice on how to do it safely. My questions fall under two categories: 1) How do I ensure that the radiation does not come in contact with human flesh, and 2) How do I detect the radiation from the x-rays. My setup: I have a directional x-ray emitter that outputs a low voltage x-ray onto an object which is captured on a screen behind it. How do I keep people safe: Lead can stop x-rays, but how thick does the lead need to be for a given x-ray intensity? Are there charts relating x-ray wavelength intensity, and wavelength to lead absorption? Lead poses another problem to human health. Are there other materials available that are dense enough to absorb x-rays, but are not poisonous to humans? I suppose that's one of the cache-22s of heavy metals. What type of eye protection is needed? Should the eyes be treated any differently than other parts of the body? Do x-rays affect the retina differently than other human tissue? How do you detect stray x-rays? I know Gieger counters can somewhat detect x-rays, but I hear only 1% of the rays. I know I can get phosphoric coatings, but is there an easier way than painting a whole room?