Radiation Resistance tests are handled in one of two ways depending on the intensity of the exposure. Background radiation exposure is handled like a Toxin Resistance test having a power between 1 and 20, set by the intensity of the background radiation (pg. 121, SR6, for more details on this type of test).
For example, Power 1 would be a poorly shielded sub-orbital transport, while Power 20 would be during a meltdown at a nuclear power plant. After every hour of exposure to background radiation, a Resistance test (Body + Willpower + the rating of any protective gear/systems) needs to be made. Very high exposure over a single combat round from a weapon or spell using radiation is handled as a physical attack with regular armor providing no protection. Any anti-radiation systems add to the user’s Defense Rating.
Filling any condition monitor box with radiation damage causes the Nauseated status until the damage is healed. Radiation damage cannot be healed with first aid, medkits, unaided natural healing, or even magic. Natural healing with medical assistance will be effective in most cases, but a glitch on the Healing test indicates that the damage is untreatable, leading to the permanent loss of the condition monitor boxes. In these cases, a cellular repair geneware treatment is required for a full recovery.