 The amount of radiation escaping the front of the monitor is widely considered not to be harmful.The Food and Drug Administration regulations in are used to strictly limit, for instance, television receivers to 0.5 milliroentgens per hour (mR/h) (0.13 µC/(kg·h) or 36 pA/kg) at a distance of from any external surface; since 2007, most CRTs have emissions that fall well below this limit.Older color and monochrome CRTs may have been manufactured with toxic substances, such as cadmium, in the phosphors.