Dirty bomb definition is - a bomb designed to release radioactive material.

. What is a dirty bomb?A dirty bomb, or radiological dispersion device, is a bomb that combines conventional explosives, such as dynamite, with radioactive materials in the form of powder or pellets. The idea behind a dirty bomb is to blast radioactive material into the area around the explosion.

This could possibly cause buildings and people to be exposed to radioactive material. The main purpose of a dirty bomb is to frighten people and make buildings or land unusable for a long period of time. Is a dirty bomb fatal?If low-level radioactive sources were to be used, the primary danger from a dirty bomb would be the blast itself. Gauging how much radiation might be present is difficult when the source of the radiation is unknown. However, at the levels created by most probable sources, not enough radiation would be present in a dirty bomb to cause severe illness from exposure to radiation. How do I protect myself and others from exposure to a dirty bomb?Radiation cannot be seen, smelled, felt, or tasted by humans. Therefore, if people are present at the scene of an explosion, they will not know whether radioactive materials were involved at the time of the explosion.

If people are not too severely injured by the initial blast, they should follow the recommendations on this page: Protecting Yourself from Dirty Bombs. How is exposure to a dirty bomb treated?Treatment for exposure to a dirty bomb is the same as for any exposure to radiological materials.

What are the long term effect of exposure to a dirty bomb?Some cancers can be caused by exposure to radiation. Being at the site where a dirty bomb exploded does not guarantee that people were exposed to the radioactive material. Until doctors are able to check people's skin with sensitive radiation detection devices, it will not be clear whether they were exposed. Just because people are near a radioactive source for a short time or get a small amount of radioactive material on them does not mean that they will get cancer. Doctors will be able to assess risks after the exposure level has been determined.

How does exposure to a dirty bomb occur?If low-level radioactive sources were to be used, the primary danger from a dirty bomb would be the blast itself. Gauging how much radiation might be present is difficult when the source of the radiation is unknown.

However, at the levels created by most probable sources, not enough radiation would be present in a dirty bomb to cause severe illness from exposure to radiation. How is a dirty bomb used?The main purpose of a dirty bomb is to frighten people and make buildings or land unusable for a long period of time. How does a dirty bomb work?A dirty bomb, or radiological dispersion device, is a bomb that combines conventional explosives, such as dynamite, with radioactive materials in the form of powder or pellets.

Shattered horizon download. The idea behind a dirty bomb is to blast radioactive material into the area around the explosion. This could possibly cause buildings and people to be exposed to radioactive material. What is the likelihood that a dirty bomb could be used?There has been a lot of speculation about where terrorists could get radioactive material to place in a dirty bomb. The most harmful radioactive materials are found in nuclear power plants and nuclear weapons sites. However, increased security at these facilities makes obtaining materials from them more difficult.Because of the dangerous and difficult aspects of obtaining high-level radioactive materials from a nuclear facility, there is a greater chance that the radioactive materials used in a dirty bomb would come from low-level radioactive sources.

Low-level radioactive sources are found in hospitals, on construction sites, and at food irradiation plants. The sources in these areas are used to diagnose and treat illnesses, sterilize equipment, inspect welding seams, and irradiate food to kill harmful microbes. What other risks are there for exposure to a dirty bomb?Some cancerscan be caused by exposure to radiation. Being at the site where a dirtybomb exploded does not guarantee that people were exposed to theradioactive material.

Until doctors are able to check people's skin withsensitive radiation detection devices, it will not be clear whetherthey were exposed. Just because people are near a radioactive source fora short time or get a small amount of radioactive material on them doesnot mean that they will get cancer. Doctors will be able to assessrisks after the exposure level has been determined. Are there any historical uses or accidents involving a dirty bomb?According to a United Nations report, Iraq tested a dirty bomb device in 1987 but found that the radiation levels were too low to cause significant damage. Thus, Iraq abandoned any further use of the device. How can people get more information about a dirty bomb?For more information about medical response to detonation of a dirty bomb, see the following page.

Terrorism works not as much by causing death as by causing fear. Bombings and shootings kill a few, or a few dozen or few hundred or even a few thousand, but frighten millions. The unpredictable random attacks in public places leave us all feeling vulnerable, afraid, just what terrorists hope to achieve. So wouldn’t you assume that among all the things that governments are doing to reduce the danger from terrorist attacks, that a big part of that effort would be to try and minimize the fear these attacks cause? You’d think so, but with one of the most fear-inducing weapon terrorists might use, you’d be wrong.The weapon is a dirty bomb, a conventional explosive mixed with radioactive material that would be dispersed across a community (it's technically known as a radiological dispersal device).

In the aftermath of the Paris attacks last November Belgian authorities that the terrorists involved in the Paris attacks were surveilling a high-level Belgian nuclear official who had access to radioactive material—not the kind that could be used to build a nuclear weapon, but perfect for a dirty bomb. And that radioactive material was stolen in Iraq last November from an oilfield company that was using the material to test the integrity of oil pipelines. No one knows who took it, or where it is.The prospect of such a bomb seems terrifying, but anyone who knows the basic science of radiation biology knows that it wouldn't cause much health damage, because the dose of radioactivity to which most people might be exposed would be very low. And experts know, based on the 65 year of the survivors of atomic bomb explosions in Japan, that even at extraordinarily high doses, ionizing radiation only raises lifetime cancer mortality rates a little bit—just two thirds of one percent for survivors who were within three kilometers of ground zero. And despite popular belief, it causes no genetic damage that is passed on to future generations.

At the low doses most people might get from a dirty bomb, the health risk is infinitesimal. Not zero, but tiny.But most people don’t know that.

They believe that any exposure to nuclear radiation is really dangerous. Radiophobia is deeply carved into public belief.

So if a dirty bomb goes off, and the global media screams with dramatic alarms about the danger of radiation, fear will spread faster and further than the isotopes of iridium or cobalt or whatever nuclear material terrorists have used. And that fear will do immense harm.Should such a weapon go off in a city, much of that city will be shut down, and major areas evacuated, for weeks or months. Tens of millions of people in the wider surrounding region, especially downwind, will be afraid. The economic costs will be vast. So will the health effects—not from radiation, but from the sweeping physical impacts of stress, including increased cardiovascular risk and weakened immune systems.

A dirty bomb will likely produce a global cry for dramatic retaliation against known terrorist havens, and heads of state will find it hard to resist. Short of the disastrous physical harm of a nuclear weapon itself, it’s hard to imagine a terrorist attack that could do more damage.So what are governments doing to protect us? They're doing a great deal to keep such a device from going off in the first place. And thank goodness those efforts have been successful, so far. But compared to the hundreds of millions of dollars being spent to prevent such an attack, practically nothing is being done to proactively defuse the fear a dirty bomb would produce. There are no attempts to put the actual danger of nuclear radiation in perspective for the public or the news media.The US (NRC) and (CDC) have websites about radiological emergencies.

(The EPA, which has significant authority over the public and environmental health effects of radiological emergencies, has practically nothing on its site about such events.) The CDC site is mostly about what to do and how to decontaminate yourself, with little about how low the risk is. The NRC statesJust because a person is near a radioactive source for a short time or gets a small amount of radioactive dust on himself or herself does not mean he or she will get cancer. Any additional risk will likely be extremely small.But posting information on a bureaucracy’s web site is hardly proactive public outreach. Much more should be done. A coordinated, persistent, multi-faceted, multi-agency communication campaign should be conducted to reach the public with this information.

A key part of this outreach should be the news media, so they understand in advance the actual threat of radiation should a dirty bomb be used. An information campaign could partner with a wide range of sources more trusted than the government; scientific, health, and medical authorities and organizations, local officials, well-known figures on social media and in popular culture, even faith leaders concerned about public well-being.

The information could be embedded in the story lines of movies and TV shows that often feature terrorist attacks in their plots. And yes, this information could be presented simply, clearly, without the technical or bureaucratic language or scientific nuance that so often interferes with effective risk communication.Would such a campaign totally dispel the excessive fear of nuclear radiation? Of course not.

The roots of that fear run far too deep to dig up entirely. But a carefully researched and carefully designed risk communication campaign could help diminish that fear, and take at least some of the power of a dirty bomb to terrorize us out of the hands of terrorists.

Governments that are working hard to protect us from such attacks must also take this important step. And soon.The views expressed are those of the author(s) and are not necessarily those of Scientific American.