Dirty Bomb Advice from an Expert – Larry Grimm
With the recent frantic coverage of the GAO’s “sting” of Nuclear Regulatory Commission licensing procedures, the phrase “dirty bomb” is again being thrown about in the popular press. I thought it was time to make the following piece readily available in another location. You might be able to find a similar document somewhere else on the web; I have lost track of where I first found it. I thought it was so important that I sent it on to my mother and asked her to share it with her friends, especially those who tend to be worriers.
(Update 7-15-2007 at 0726: I did a bit of Googling and found another posting of the original piece on a web site called Doctors for Disaster Preparedness. Here is the link – http://www.ddponline.org/dirtybomb.htm)
FORMER SAILOR SHARES INSIGHT ON PROTECTION AGAINST DIRTY BOMBS
Timmi Toler, Community Editor, The Liberty
With recent reports that radiation detectors are being tested in our community, many residents are wondering how to be prepared or what to do in the event that a radiological dispersion device (or “dirty bomb”) is detonated. The Liberty turned to Larry Grimm for some answers. Grimm, a former Navy Reservist who served as a corpsman with the 1st Marines, Recon Battalion, Alpha Company, is now the senior health physicist for the Radiation Safety Division at UCLA. He has 27 years experience working with a wide variety of radioactive materials and their uses. He offered his personal insights to the following questions to help equip citizens with what he considers the most effective tool available in the fight against terrorism: knowledge.
Q: What is a radiological dispersion device?
A: It is a weapon designed to spread radioactive material over an area. Radioactive materials can be spread via a conventional (“dirty”) bomb, an aerosol device or through waterways.
Q: What is the biggest concern from a radiological dispersion device?
A: Two things: the irrational fear it can induce and the expense of cleanup. The possibility of the radiation actually hurting anyone is quite small. We fear what we do not understand, sometimes irrationally. The concepts of radiation are poorly taught in high school, and the only other radiation information we get has been sensationalized by Hollywood, politicians, and those looking to make a buck off of our lack of education. You can beat the fear by learning how radiation works and how to manage it safely (protection techniques). Fear and panic kill people, as any good Marine knows. Radioactive materials are chemicals. Sometimes it is easy to clean them up, sometimes hard. For example, cleaning oil off concrete is hard, but picking up chunks of metal is easy. Fortunately, it only takes a radiation detector to find the radioactive material, so it is easier to find and clean up than a non-radioactive chemical. Likely, the biggest problem will be economic disruption while cleanup takes place. Radiation dispersion devices are really disruption, not destruction, weapons.
Q: How will I know if something is a radioactive device/bomb?
A: You won’t know, until someone checks and announces it. Most police and fire vehicles carry radiation detectors these days and the announcement is likely to be made quickly. If a bomb went off, I would presume the worst and start practicing the protection techniques listed below. The techniques are also applicable, to a certain extent, if there is a chemical or biological agent, however, there are a few important differences. For example: if you suspect a chemical agent, do not seek shelter in a low space (like a basement). Most chemicals are heavier than air and will settle in low spaces.
Q: What steps should I take if a radiological dirty bomb goes off in the area?
A: There are four simple protection techniques: Contamination control, distance, shielding and time. Contamination control and distance are the most useful techniques in a bomb situation.
Remember to help others first. Radioactive materials are rarely immediately life threatening. The worst-case terrorism scenarios indicate that there would not be enough radioactive material to cause immediate harm. Did you ever feel anything or see an effect from getting an X-ray? In 99.999% of radiation exposures, no effect is felt or seen. If I went towards the blast area to help someone, I would not fear the radiation. However, I would be cautious and respectful of the radiation. Therefore, I would use the following techniques no matter if I was escaping the area, trapped in the area, or going in to help.
Contamination control: Keep the radioactive chemical off and out of your body. Button up clothing and wear a mask (or anything to cover nose and mouth.) A radioactive material is always a chemical, which behaves like the chemical wants to behave. The distance technique is the best protector in a dirty bomb scenario. However, if I need to be near the source, or if I am downwind of the blast, I will first practice contamination control. If I suspect that I swallowed or inhaled the chemical, but do not feel ill, I would later seek professional help. Radiation effects take a long time to show up, and I wouldn’t want to add to the congestion at the hospital. However, there could be a nasty chemical associated with a radioactive bomb, so if I felt even slightly ill, I would seek medical help in a hurry.
Distance: In even the worst bomb scenario, you would be safe from the radiation if you get just a couple blocks away and get upwind of potential airborne material. Think of it as standing next to a campfire – get too close to the heat radiation, and it could burn you, but if far enough away, you do not get any heat. Exactly like a campfire, you do not want to be in the smoke, so get upwind. The most likely radioactive material in a dirty bomb would be Cobalt or Cesium. If the terrorist could somehow manage to get 10,000 Curies in the bomb, you only need to be about 300 yards (three football fields) away to be safe from the radiation. If you are not downwind or near the dispersion area, you are safe. Do not “head for the hills”. Leave the roadways open so emergency responders can get through.
Shielding: Anything acts as a shield – a building, a car, a hill, et cetera. Your major concern is gamma radiation. Imagine the gamma as a radio wave. When don’t you get a radio signal? When you are in the middle of a building, in a basement, behind a hill, et cetera. Whatever shielding decreases a radio signal will decrease gamma rays. I handled 12 million curies of Cesium (a 1000 times more than a possible bomb) with a mere 20 feet of water for shielding, and I got no dose!
Time: The less you are around the radiation, the less dose you will get. As most people would use distance, and get away in a hurry, they already used the time technique by not hanging around the radiation. Emergency responders may need to use this technique, and all across the US, they are receiving training on how to use it.
Q: If you suspect the chemical is on your clothes or body, what should you do?
A: First, simply remove the clothing. Take off the clothing, put it somewhere distant, and you will get no exposure from what is on the clothes. A common myth is that if radiation hits someone, they become radioactive. The reality is: it is the radioactive chemical that makes you radioactive, not the radiation, so you want to keep the chemical off yourself.
Second, wash or shower. Most radioactive materials are easily washed off. Another common myth is that you need to scrub hard to get radioactive material off you. In actuality, you should wash lightly and frequently. Scrubbing hard can abrade the skin and push the chemical into the body. When I practiced Nuclear Medicine, almost every day I got radioactive material on my index finger. With a light washing, it went away every time. Twenty-five year
s later, my finger is just fine, and still willing to point a Marine towards the vaccination line (a corpsman’s pay back for being called “squidly”)!Q: If I am trapped in my house with my children and downwind of the dispersion device, what do I do?
A: How do you keep dust and cold air out of your house? Simple – make sure things are shut tight. It’s the same with radioactive materials. Stay put, and hunker down. The downwind concern is that the radioactive chemical is airborne. Keep the chemical out of your house and you will be quite safe. Keep doors and windows closed. You might move to the middle of the house or basement, which uses the distance and shielding protection techniques, in case there are levels of radiation nearby. If you must go out, use the time technique and do your task quickly. If the radioactive chemical is heavy, or it is raining, the chemical will not travel far by air, so if you are more than a mile away, there would likely be no problem. In the likely scenarios which use Cobalt or Cesium, they are heavy and do not travel too far in the air. Listen to your radio, as emergency information services should soon tell you if it is safe to go out. Boredom will be your biggest problem.
Q: If I am outside and downwind of the blast and cannot move quickly, what do I do?
A: Get into the nearest building and do what you would do in your house – keep things shut and move to middle room or basement areas. Another option is to get in or stay in your car with windows up and fresh air vents closed. You will keep the chemical out, and the car provides some shielding. If it is hot in the car, recirculating air conditioning is okay to use. If you can move the car, drive a few blocks away.
Q: Will my food become radioactive?
A: Not if it is sealed or covered. Again, another myth about radiation is that it causes other things to become radioactive. The truth is this only happens if the chemical gets on it. I would keep bottled water and a few canned goods for emergencies, but the way food is packaged these days, the foods in your cupboards and refrigerator will be just fine. For extra measure, you can rinse things off before you open/use them, but most likely this is not necessary if you have kept the house closed up.
Q: What should I get to prepare for a dirty bomb?
A: Not much. Keep some bottled water on hand and a portable radio. Do not buy a radiation meter. Do not buy special contamination suits. Do not buy gas masks. Only trained professionals should have these things. Untrained people have been hurt by these things. Can you imagine the horror and grief of a child suffocating in a gas mask, especially if the radiation was three miles away? The simple protection techniques are all you need. They work. I know. I use them every day in my work. Use your common sense when applying the techniques and you, and your children, will be very safe.
Q: What are the odds of a radiological dispersion device going off in my area?
A: Pretty slim. A radiological dispersion device is unlikely to kill anyone, unless it is a bomb and the person is in the blast area. Therefore, it is a poor “mass destruction” weapon. On the other hand, it can disrupt things badly, particularly if we respond with fear and panic. Although its not hard to build a radiological dispersion device, it is difficult to carry around the large quantity of radioactive material necessary.
Q: What if the radioactive material is put in our water supply?
A: Being a chemical, the radioactive material will dilute in the water. Without going into technical reasons, suffice it to say that by the time it got to your house, there wouldn’t be enough to pose a real risk. Smoking one cigarette probably poses more risk than the amount of radioactive material that you could ingest in this scenario. We ingest naturally occurring radioactive materials every day of our lives. Likely by the time it got to you, the terrorists’ material would be a pittance of what you normally, naturally take in. Another common misconception is that man-made radioactive materials are different and more dangerous than natural materials. However, there really is no difference. Man-made and natural radioactive material effects are the same. Our bodies are adapted to handling the effects of low levels of radiation, which we receive every moment of our lives. If it is suspected to be in the water supply, and you are concerned, use bottled water. I would likely have no fear of showering with the tap water.
Q: Any final thoughts?
A: Please teach these simple things to others. As more people learn how easy it is to protect themselves from a radiological dispersion device, our collective fear levels decrease. Learn about radiation, and the fear of it will melt away. As a youngster, I feared electricity, but I learned it can be handled safely. I now respect it, but do not fear it. The same is true of radiation: respect it, but do not fear it. Terrorists feed on fear. Fear is bondage, knowledge is freedom.
“LEARN ABOUT RADIATION, AND THE FEAR OF IT WILL MELT AWAY …TERRORISTS FEED ON FEAR.
FEAR IS BONDAGE, KNOWLEDGE IS FREEDOM.”LARRY GRIMM
Senior Health Physicist for Radiation Safety Division, UCLA
