Subnucleonic radiation is a form of radiation that causes severe burns to the skin and disorientation in most lifeforms. Prolonged exposure will usually result in death. There is almost nothing that can be done to prevent the radiation from affecting the body. Only being held in stasis while navigating through this radiation will prevent the effects of subnucleonic radiation.
In 2374 the crew of the USS Voyager discovered a Mutara class nebula that emitted subnucleonic radiation and soon discovered its effects. One crewmember died on the Voyager bridge during this exposure. The only person not fully affected by the radiation was Seven of Nine due to her Borg-enhanced physiology, though over time it started to affect her sensory nodes, causing hallucinations.