question: How is radiation decontaminated?
comment: Radioactive contamination works by two methods: 1) Neutrons and occasionally alpha particles being smashed into less or non-radioactive atoms hard enough to stick, converting the less or non-radioactive atom into a more radioactive one. 2) Bits of the radioactive material used falling off and being left behind. The good thing about both of these things is that the actual contamination in both cases is either chemically different from it's surroundings, or about to become chemically different from it's surroundings by decaying into a different element. To remove contamination, all you have to do is spray the area in something that'll remove contamination more easily than the material it's on. Air and water works quite well in many cases, though if the radiation gets inside something that air and water can't penetrate (you, for example) various other chemicals are used the most popular of which is potassium iodide. Alternatively you can just wait for all the contamination to decay to something that's less radioactive than you, your food, and the air you breathe is. Ever since we started burning fossil fuels and importing bananas, the time it takes to do so has been getting shorter and shorter, though it does still take a while.
passages: Human decontamination
  
  Human decontamination is the process of removing hazardous materials from the human body, including chemicals, radioactive substances, and infectious material.
  
  Section::::General principles.
   Surface contamination may either be fixed or "free". In the case of fixed contamination, the radioactive material cannot by definition be spread, but its radiation is still measurable. In the case of free contamination there is the hazard of contamination spread to other surfaces such as skin or clothing, or entrainment in the air. A concrete surface contaminated by radioactivity can be shaved to a specific depth, removing the contaminated material for disposal.
   For this reason, it is important to use personal protective equipment when working with radioactive materials. Radioactive contamination may also be ingested as the result of eating contaminated plants and animals or drinking contaminated water or milk from exposed animals. Following a major contamination incident, all potential pathways of internal exposure should be considered.
  
  Successfully used on Harold McCluskey, chelation therapy and other treatments exist for internal radionuclide contamination.
  
  Section::::See also.
  
  BULLET::::- Contamination control
  
  BULLET::::- DeconGel
  
  BULLET::::- Decontamination foam
  
  BULLET::::- Disease surveillance
  
  BULLET::::- Fukushima disaster cleanup
  
  BULLET::::- Incident Support Unit
  
  BULLET::::- Mass decontamination
  
  BULLET::::- Radioactive contamination
  
  Section::::External links.
   From this process, some strategies have been designed based on sequences of ponds with a slow flow of water to clean polluted water with radionuclides. The results of these facilities, for flows of 1000 liters of effluent are about 95% retention of radiation in the first pond (by plants and sludge), and over 99% in three-base systems.
   Mass decontamination is the decontamination of large numbers of people. The ACI World Aviation Security Standing Committee describes a decontamination process thus, specifically referring to plans for Los Angeles authorities:
  
  Section::::Hospital decontamination.
   Cleaning up contamination results in radioactive waste unless the radioactive material can be returned to commercial use by reprocessing. In some cases of large areas of contamination, the contamination may be mitigated by burying and covering the contaminated substances with concrete, soil, or rock to prevent further spread of the contamination to the environment. If a person's body is contaminated by ingestion or by injury and standard cleaning cannot reduce the contamination further, then the person may be permanently contaminated.
   Irradiation is the use of ionising gamma rays emitted by cobalt-60 and caesium-137, or, high-energy electrons and X-rays to inactivate microbial pathogens, particularly in the food industry. Bacteria such as "Deinococcus radiodurans" are particularly resistant to radiation, but are not pathogenic. Active microbes, such as "Corynebacterium aquaticum", "Pseudomonas putida", "Comamonas acidovorans", "Gluconobacter cerinus", "Micrococcus diversus" and "Rhodococcus rhodochrous", have been retrieved from spent nuclear fuel storage pools at the Idaho National Engineering and Environmental Laboratory (INEEL). These microbes were again exposed to controlled doses of radiation. All the species survived weaker radiation doses with little damage, while only the gram-positive species survived much larger doses. The spores of gram-positive bacteria contain storage proteins that bind tightly to DNA, possibly acting as a protective barrier to radiation damage.
   BULLET::::4. Radium Removal: Some groundwater sources contain radium, a radioactive chemical element. Typical sources include many groundwater sources north of the Illinois River in Illinois. Radium can be removed by ion exchange, or by water conditioning. The back flush or sludge that is produced is, however, a low-level radioactive waste.
   To help with environmental remediation, one can get environmental remediation services. These services help eliminate radiation sources in order to help protect the environment.
  
  Section::::Remediation standards.
   Mass decontamination
  
  Mass decontamination (abbreviated mass decon) is the decontamination of large numbers of people, in the event of industrial, accidental, or intentional contamination by toxic, infective, caustic, polluted, or otherwise unhealthful or damaging substances.
  
  Section::::Mass hysteria and security aspects.
   Section::::Bacterial bioremediation.:Bioreduction.:Citrate complexes.
   Separate male and female dofficers (decon officers) deal with potentially unruly patients, by restraining the hands using flex cuffs, and cutting off the shirt, then removing shoes and pants normally. This usually requires a couple of officers.
  
  The Belfast Telegraph describes such a situation:
  
  See also Battalion Chief Michael Farri:
  
  Section::::Internal human contamination.
  
  Radioactive contamination can enter the body through ingestion, inhalation, absorption, or injection. This will result in a committed dose of radiation.
   Section::::Methods.:X-Ray IORT.
   Some of the largest areas committed to be decontaminated are in the Fukushima Prefecture, Japan. The national government is under pressure to clean up radioactivity due to the Fukushima nuclear accident of March 2011 from as much land as possible so that some of the 110,000 displaced people can return. Stripping out the key radioisotope threatening health (caesium-137) from low level waste could also dramatically decrease the volume of waste requiring special disposal. A goal is to find techniques that might be able to strip out 80 to 95% of the caesium from contaminated soil and other materials, efficiently and without destroying the organic content in the soil. One being investigated is termed hydrothermal blasting. The caesium is broken away from soil particles and then precipitated with ferric ferricyanide (Prussian blue). It would be the only component of the waste requiring special burial sites. The aim is to get annual exposure from the contaminated environment down to one millisievert (mSv) above background. The most contaminated area where radiation doses are greater than 50 mSv/year must remain off limits, but some areas that are currently less than 5 mSv/year may be decontaminated allowing 22,000 residents to return.
   Section::::Source melting.
  
  In the case of some high-value scrap metals it is possible to decontaminate the material, but this is best done long before the metal goes to a scrap yard.
  
  Section::::Source melting.:Ferrous scrap.
   Exogenous infections can be caused by organisms that colonize the skin such as "Staphylococcus aureus" or "Streptococcus" spp. and organisms that are acquired from the environment such as "Pseudomonas" spp. 
  
  Organisms causing sepsis following exposure to ionizing radiation:
  
  Section::::Principles of treatment.
   The primary excretory pathway for phosmet is through the urine or feces, with greater than 70% of the compound being excreted through the former and about 4.5% to 9.9% being excreted in the latter; by 12 hours, more than 50% of the radioactivity can be seen to have been eliminated from an animal organism. There also seems to be a relationship between the dose given to an organism and the excretion of the compound as well the radioactivity; in live animal studies it is observed that at a higher dose, excretion of the compound is significantly slower than at lower doses. Inversely, there is a higher reported radioactivity with acute exposure rather than repeated exposure.
   It has been estimated that sixteen feet (5 meters) of Mars regolith stops the same amount of radiation as Earth's atmosphere.
  
  Section::::Overview.:Power.
   For this reason, it is important to use personal protective equipment when working with radioactive materials. Radioactive contamination may also be ingested as the result of eating contaminated plants and animals or drinking contaminated water or milk from exposed animals. Following a major contamination incident, all potential pathways of internal exposure should be considered.
  
  Successfully used on Harold McCluskey, chelation therapy and other treatments exist for internal radionuclide contamination.
  
  Section::::Decontamination.
   BULLET::::- A person who is being treated for cancer by means of an "unsealed source" radiotherapy method where a radioisotope is used as a drug (usually a liquid or pill). A review of this topic was published in 1999. Because the radioactive material becomes intimately mixed with the affected object it is often difficult to decontaminate the object or person in a case where internal exposure is occurring. While some very insoluble materials such as fission products within a uranium dioxide matrix might never be able to truly become part of an organism, it is normal to consider such particles in the lungs and digestive tract as a form of internal contamination which results in internal exposure.
   The initial scope of the OSR Project included all Greater than Class C (GTCC) sealed sources. However, since September 11, 2001, the mission expanded from environmental concerns to public safety and national security. As a result, OSRP direction and oversight moved from the Department of Energy's (DOE) Office of Environmental Management, to the National Nuclear Security Administration in 2003. 
  
  The project mainly addresses sources containing americium and plutonium. The recently expanded mission also includes recovery of beta or gamma emitting sources, like caesium and strontium. 
   In dairy farming, one of the best countermeasures against Cs is to mix up the soil by deeply ploughing the soil. This has the effect of putting the Cs out of reach of the shallow roots of the grass, hence the level of radioactivity in the grass will be lowered. Also after a nuclear war or serious accident, the removal of top few cm of soil and its burial in a shallow trench will reduce the long-term gamma dose to humans due to Cs, as the gamma photons will be attenuated by their passage through the soil.
   After filling a cylinder, a seal is welded onto the cylinder head. The cylinder is then washed. After being inspected for external contamination, the steel cylinder is stored, usually in an underground repository. In this form, the waste products are expected to be immobilized for thousands of years.
   Decontamination
  
  Decontamination (sometimes abbreviated as decon, dcon, or decontam) is the process of cleansing an object or substance to remove contaminants such as micro-organisms or hazardous materials, including chemicals, radioactive substances, and infectious diseases.
  
  The purpose of decontamination is to prevent the spread of micro-organisms and other noxious contaminants that may threaten the health of human beings or animals, or damage the environment.
  
  Decontamination is most commonly used in medical environments, including dentistry, surgery and veterinary science, in the process of food preparation, in environmental science, and in forensic science.
  
  Section::::Methods.
  
  Methods of decontamination include:
  
  BULLET::::- Physical cleaning
   BULLET::::- A person who is treated for cancer by either teletherapy or brachytherapy. While in brachytherapy the source is inside the person it is still considered external exposure because it does not result in a committed dose.
  
  BULLET::::- A nuclear worker whose hands have been dirtied with radioactive dust. Assuming that his hands are cleaned before any radioactive material can be absorbed, inhaled or ingested, skin contamination is considered external exposure.
  