This article was written by experts. Specifically, the health physics team in charge of protecting workers, monitoring releases and recording doses at Three Mile Island during the month after the worst nuclear accident in American history.
2011 was the year when average people all over the world were suddenly confronted with the very real and serious dangers to human health presented by "peaceful" applications of nuclear technology. The triple meltdowns and subsequent explosions at the Fukushima Daiichi reactor complex in March sent plumes of radioactive contamination across the northern Japanese countryside and high into the atmosphere to blanket the entire northern hemisphere with dangerous fission product isotopes most people had never heard of before.
Confusing and contradictory reports from officials around the world left too many people unsure of what dangers they and their families face from fallout, the actual levels of radioisotopes in their air, food and water supplies, and how those will continue to present dangers for decades (and, in some places in northern Japan, centuries) to come. The pro-nuclear lobby repeatedly claims that radiation exposures are "harmless" or even "good for you," academic experts have insisted just as repeatedly that there is no âsafe' level of exposure. Whom should we believe?
Since it is often true that the best defense is a good offense, here are 15 practical methods of reducing exposures to radiation and radioactive contamination in homes, schools and offices, from a group of health physics personnel, the technicians charged with exposure control at nuclear facilities of all types. The techniques are effective whether the exposure is acute – an accident or release at a nuclear facility nearby that is not expected to be long-term – or chronic low-level exposure such as from fallout caused by major accidents or bomb explosions.
You need not own a radiation detector* to monitor actual levels in order to practice these techniques as a matter of habit, and they will be effective even against other natural and unnatural pollutants/allergens that may be ubiquitous where people live. One thing Fukushima has taught us is that âofficials' are not trustworthy for providing accurate and timely information about radiation levels – or the presence of toxic effluents from other industries and accidents – to the public. Thus it is best in times of uncertainty to err on the side of precaution.
* Since Fukushima several inexpensive models of hand-held low-level radiation detectors have come on the market, including at least two downloadable applications for high-end cell phones that are fairly accurate and recommended for people who live within 50 miles of a nuclear facility. Which, in the United States, includes an estimated 116 million citizens.
Radioactive particles are much smaller than even the tiniest dust particles and cannot be seen. But if you assume that all the dust in your indoor environment is radioactive, careful cleanliness will protect you against excess exposure from unseen particles as well.
1. It can help to visualize a layer of invisible dust even when surfaces look clean and shiny. You will want to wash the walls, counter tops, furniture and appliance surfaces and floors regularly. Each time, use a clean mop and sponge, keep a good supply of paper towels, plastic grocery and trash bags, and sturdy trash containers with tight-fitting lids on hand.
Always wash from top to bottom, at least once a day. Dispose of all used mop heads, sponges and wipes in a trash container outside. DO NOT dry-dust or sweep or use a feather-type duster, as these will simply cause dust (and isotopes) to become airborne where they can be inhaled or settle onto food, etc.
Carpets, Rugs and Mats
Most people are aware that carpets, rugs and floor matting are dust-magnets. These cannot be washed daily in an effective manner, and often cannot be removed for the duration of the danger. Daily or twice daily vacuuming is recommended, but be careful of older vacuum cleaners that often have âleaks' that stir more dust into the air than is sucked into the bag.
2. A good filtered vacuum is baseline requisite. Replace the filter regularly with the finest grain filter available for the unit, and wash it carefully after each use even if it doesn't look dirty. Place all disposed filters and dust bags in tightly closed plastic grocery bags in a trash bag lined, closable outdoor container. You do not want concentrated contaminates from cleaning to remain inside.
A water-filtered vacuum is preferable to a regular vacuum if you can get one. Good shop-vacs will work for this. Dispose of contaminated water down the toilet, then clean the toilet – including seat – thoroughly with fresh water. Also, a water-filtered or virus-rated air filtered indoor air purifier is a good idea to run several times a day following your cleaning regimen. This will remove dust that cleaning activity has caused to go airborne.
In The Kitchen
The danger of ingesting radioisotopes is significant, as internal contamination is 20 to 100 times more harmful than external exposures. Alpha and beta particle radiations do not present significant external exposures at all in low levels, but once they get into your body they can easily damage or destroy sensitive cells. Thus some careful kitchen habits will go a long way toward limiting internal exposures.
3. Always keep your pots, pans, plates, silverware and utensils in clean cabinets with doors/covers, drawers or covered containers such as Tupperware bins. Remove coverings carefully so as not to shake the dust they may have accumulated out into the air or onto previously clean surfaces.
4. Always rinse your cooking utensils, plates, silverware, glassware, etc. in clean – preferably filtered – water before using them. The best filters for the purpose use activated charcoal or reverse osmosis, as these are quite effective at trapping the most dangerous radioisotopes. Change the filter every two or three days during the entire course of the radiological emergency. Wrap used filters in tightly closed plastic grocery bags and keep them in the lined âhot trash' container outdoors.
5. Be sure to rinse the outside of all food cans before opening (with a well-rinsed manual can opener). Wipe rinsed articles off with a paper towel and dispose of those in the same outdoor âhot trash' container.
Coming and Going
Every time a human or pet comes into the indoors from the outdoors, they will be bringing contamination with them. Limiting this new source of contamination is important to limiting indoor exposures.
6. When you go outside, wear a set of coveralls or a duster over your clothes. Rubber boots over shoes is a good idea as well, especially if it is raining. Fallout contamination in rain can be 10-20 times higher than it is in clear weather. A pair of outdoor shoes is also recommended. None of these items should come inside, but should be left outdoors on a porch or landing, or confined to the entry area.
7. Shower every time you come indoors from having spent more than a few minutes outdoors. Always wash from top to bottom, and don't ingest any of the wash water. Avoid breathing steam by using cool, lukewarm or just slightly warm water.
8. Obtain a supply of good quality dust masks to cover your mouth and nose, and ALWAYS wear it when outdoors or traveling in your vehicle. A utility painter's type mask is better than a flimsy medical type mask, available from hardware and home improvement stores. Or you may choose to use handkerchiefs if they are made of a tightly woven fabric. Fold it to provide more than one layer of cloth and cover mouth/nose as tightly as possible and still allow breathing.
General Air Flow
The "Shelter In Place" advisory we heard about for citizens outside the evacuation zone around Fukushima was intended to limit residents' exposures to the radiation levels outdoors. It did not work very well due to public ignorance of the need to keep outdoor air and contamination out of indoor spaces, but the basic premise is sound if these listed methods are followed carefully, along with all other recommendations given here.
9. Seal all doors that open to the outside with duct tape. Use only one door for entering and exiting, preferably a door that enters into a semi-enclosed entry space, garage or âmud room'. Make that space into a "change over" area for protective outdoor clothing and footwear.
10. Windows should also be tightly closed (even if it's nice outside) and sealed with duct tape for the duration of the emergency. Run your air conditioner at least 12 hours a day using the "recirculation" setting, even when you are not using the heat or cooling cycles. Get fine filters and change them daily. If using foam filters, these may be carefully washed and allowed to dry after changing, but fine-grain fiber dust filters that are disposed of as âhot trash' after changing are better.
Do NOT use fans to blow outside air in, or run AC units on settings that draw outside air inside. Take steps to keep indoor air from being too dry. A semi-humid environment lets water vapor attach more particulate contamination and bring it down to floor level so it's not floating around where you are breathing.
Pets and Short People
Dogs, cats and small children are much closer to the ground than upright adults and will tend to absorb more contamination. What may be a non-dangerous "extremity dose" to an adult walking with his or her head well above the ground can present a contamination danger to crawlers, toddlers and pets – especially dogs, who are prone to sniffing the ground regularly.
11. Always carry young children while outdoors or going to and from a vehicle. Avoid taking them out in the rain if at all possible, and do have them wear mask, hat and some kind of outer covering like a duster, blanket or coat. At home, try not to let children spend a lot time on the floor. If they must be on the floor, spread a clean sheet onto it first.
12. Keep pets indoors as much as possible for the duration. If you must let the animal outside for a period of time (keep it short), keep a wash tub near the door along with a supply of clean towels. Wash them down (top to bottom) before bringing them indoors, where you can towel them off. Keep a closed hamper in or just outdoors of your entry zone to receive used towels and outer clothing bound for the laundry.
13. All family members (including pets) should sleep at least two feet above the floor for the duration of the emergency – or for as long as there are reports or suspicions of elevated radiation levels – to keep radioactive contamination well away from nose and mouth. You may have to let the dog sleep on the couch to accomplish this, so do cover your couch or other likely animal bed surfaces with clean sheets and change them daily.
14. Regular laundering of sheets, handkerchief masks, outdoor clothing, etc. should keep them fairly free of contamination. But wash the more contaminated items separately from regular laundry so as to avoid possible excess contamination to all your laundry. DO NOT hang clean laundry on an outdoor clothesline. Use your dryer (and clean the filter after every load, treat the lint as âhot trash') or hang indoors overnight to dry.
15. Keep following all these procedures for several days or even a week or two after the "danger" appears to have passed, as residual radiation and contamination may still be in the environment. wrestling the kids out on the lawn or splashing around in mud puddles may be fun pastimes you must give up for a long while.
Depending on the isotopes present in the environment, the danger may persist for months or years. A radiation detector is handy for locating hot spots in and around your property, and these will tend to be found in normal drainage pathways such as eave gutters, underneath downspouts and along drainage ditches. If you find any of these, avoid them carefully until you or some official remediation outfit can effectively decontaminate them.
Do not attempt decontamination or remediation yourself unless you know what you're doing and take serious precautions for your own safety. Remember, some common isotopes have long half-lives and will tend to concentrate to remain dangerous for centuries. If it looks like this is to be the situation where you live, it may be for the best to relocate farther from the source. This can be especially true for those who grow food or raise livestock on the land. Some nasty isotopes are readily uptaken by food plants and concentrate in them to present internal hazards to all who consume them.
No one but you can make such a decision for the long-term well-being of self and family, and it's a hard decision to make. The world has not faced such serious contamination concerns since the atmospheric bomb testing days and the accident at Chernobyl in 1986. Contamination from Fukushima will be with us for many years.
These simple health physics techniques can help minimize exposures, but the best protection is to avoid exposures in the first place. Toward that end, I wish us all the best of luck.
Discover more about this topic with the book Home Health Physics