Archive for December, 2010

There seems to be much interest in the rising possibility of disruption to our daily lives through a large scale EMP event, whether through natural means such as a solar storm or through terrorist inflicted damage via a high altitude detonation of as nuclear device, otherwise known as a HEMP attack. And along with that rise in interest in the event comes an increase in the amount of advice on how to protect ourselves against such an event. Unfortunately, much of it isn’t quite true.

What exactly would happen in one of these events? In the most severe event that we could expect, a Coronal Mass Eruption or Ejection, a huge wave of electromagnetic disturbance would arise from the suns surface and speed towards the earth. This wave would contain hundreds of thousands of volts at incredibly high amperage levels, much higher levels than most surge protection equipment could handle that is in use today. Look at that little plug strip you plug your computer into for protection. I won’t go into all the details behind how it works and all, but you can read about how these surge protectors work here.

In simple terms, a metal oxide varistor channels high amperage voltage and current to the earthing ground of a circuit, thus dissipating any damaging current and keeping your equipment safe. There is more than one type of ground that can be implied when the term ground is used. One type of ground is the signal ground, the second type is the chassis ground, and the third type is called the earth ground. The third type is the one that is important here. Unfortunately, many people group all three grounds together, and that is where much misinformation gets spread. What you want to concentrate on when making your preparedness plans to survive such an event is making sure that whatever type of protection you use, that protection is solidly connected to some kind of earth ground system.

Perhaps the best way to learn about protecting yourself from these events is to jump into the way-back machine and read all about lightening protection and the Faraday Cage. The Faraday cage was invented by Faraday back in 1836, so it’s not a brand new theory, and we know it works- when constructed properly. Even today, modern high rise buildings are constructed as giant Faraday Cages to protect the structure and its occupants against lightning strikes. We can in fact protect ourselves from these events, but that protection doesn’t come cheap. And it is not always going to come easily, especially if you want widespread protection.

Our national infrastructure is the largest scale challenge, and the technology exists to provide that protection, but not the funding. With that in mind, our best course of action is to protect our own butts, and leave the infrastructure to others. These EMP bursts, pulses or waves, whatever you chose to call them will race through the atmosphere looking for something to take them to the earth or ground. They find that path through metal structures or elements such as wires and steel buildings, buildings and tall trees, or human beings, as in the case of lightning. But the damage from some of these EMPs will be far greater, as the voltage and amperage will be far greater than a lightning strike would be.

The secret to EMP protection is to be able to siphon as much current as possible to the earth ground where it will be dissipated, for one thing, and for another to segregate your electronic devices from any voltage/current potential by wrapping and grounding the packages. The design for a secured grounding grid with an in ground web can get pretty complicated, but visualize a lightning protection circuit (LPC) for your home. Susan Bronson wrote a very good, but quick article in Popular Science with a brief description on an LPC that you can access here. I’ll also suggest you read Plain directions for the construction and erection of lightning-rods by John Phin.

The difference between a standard UL approved system for lightning protection and EMP protection is that you may require larger gauge conductors, and you will definitely need a large scale buried ground web of buried cables and ground rods. As to how much bigger, and how big of a web you need, I’ll refer you to a licensed electrical engineer. To help out, refer to this system as an isolated ground system similar to that used on commercial computer mainframe and control systems. And just as a warning, it’s not going to be cheap, but your home will be protected.

You will also have some problems with solar panels and generators, both gas and wind powered because of the coils of wire on the motor windings, as well as the wires connected to the equipment. Run the conductors leading to your home in metal conduit, and construct a metal mesh cage to completely surround the equipment. Solder leads to the mesh and ground them to the conduit. The generator shouldn’t be a big problem, but the wind turbines will obviously have to have one end of the housing where the shaft exits the housing to allow the blades to freely rotate. There’s nothing you can do about that, so be prepared to make repairs as needed. Solar panels will also be a problem as there really isn’t any way to construct a tight enough mesh over the cells without blocking the light, reducing the unit’s efficiency. I would suggest here that you use a one inch mesh made from a small diameter wire and hope for the best. There may be by now a source for some sort of protective equipment, but I’m not aware of any on the market at this time.

As to your electronic devices, which will surely be subjected to fatal damage in an EMP event, do not leave the plugged into the power supply if you can help it. Also make sure to remove any antennae if possible. Electrical currents will be seeking the path of least resistance, and wires and antennae look like a geek cruising the bad part of town with a fifty dollar bill hanging out the window. Make some electrically insulated bags or boxes to put your equipment in. One item per bag is the safest. You can make these out of rubber sheets; just make sure that the bag is 100% closed to prohibit leakage of stray current. Then place them into some metal screen mesh bags that are also securely closed with no gaps.

If you have a super sensitive device, or high value item such as a laptop with your entire life detailed on it, place these bags into a larger rubber bag and finally cover with a larger screen mesh bag. This screen mesh can be regular window screen, but it has to be metal, not fiber material. Copper is a better conductor, but steel will work also. In a future post I’ll share some designs and construction tips for these bags.

Like I said, there are a lot of things we can do to protect our own butts from an EMP event, but the real problem will come from the failure of the public infrastructure systems. It will be very costly to install these protections, so I really don’t see them in use any time soon. Just remember that the key is to devise a way to siphon off all of that current these events will generate, and funnel them to the earth/ground where they will be safely dissipated. Don’t panic, talk to a professional that knows about grounding systems, especially when it comes to lightning protection as these folks will have the expertise that can help you develop a plan for your situation.

Some people are going to fluff off what I’ve said here as being too simple and old fashioned, but solutions don’t always have to be complicated. They do, however have to work, and if lightning protection systems can keep a skyscraper safe from strikes because they are built as a Faraday Cage, then it will work for you too.

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Reading expiration dates on all of those cans in your pantry:

One of the worst headaches food storage can provide is how to deal with all of those dates and codes on the many cans, boxes and bags of food you have in your pantry.

Let me give you a few examples from my own pantry and then I’ll decode them for you.

These all have easily readable codes:

  • Armour Vienna Sausages     best by June 09 13 (of10 211w p4247)
  • Armour Chopped Ham         best by 07-14-11 (fm14g809:36 103 est-2ad)
  • Dinty Moore Meatball Stew    best by Jan 2013 (est 199g t128194 15:31)
  • Libby’s peas and carrots    (g9mj131a 1115 4307 peas/carrots)
  • Chicken of the Sea Tuna    best by 08/20/13 (gal3d 1a22a 10:03)
  • Heinz Yellow Mustard         10/28/2011 (hfog27q9 15:46)

I tried to find some weird coded cans but out of the few dozen cans in my pantry there were none, so sorry about that. It seems that pretty near all of the processors now use actual dates on their packaging. The codes accompanying the dates are mostly production dates and lot numbers. Generally speaking, all of these products should be acceptable for at least two to three years after the sell by date. The general consensus is that properly sealed canned goods tend to have an indefinite shelf life, however you should keep in mind that flavor, appearance and nutritional value does degrade after a period of time in any canned good. So more so than others, but that’s where you need to do your own research into the matter.

Let’s look at some of the fallacies and fact behind canned food storage. Many people labor under the assumption that a can of food must be tossed in the trash if it is past the date printed on the can. This doesn’t necessarily have to be the case. There are three general terms used for dating canned goods in practice;

Types of Dates

  • A “Sell-By” date tells the store how long to display the product for sale. You should buy the product before the date expires.
  • A “Best if Used By (or Before)” date is recommended for best flavor or quality. It is not a purchase or safety date.
  • A “Use-By” date is the last date recommended for the use of the product while at peak quality. The date has been determined by the manufacturer of the product.
  • “Closed or coded dates” are packing numbers for use by the manufacturer.

While all of these codes suggest when a product should be sold by, they don’t specifically tell you whether the food is safe or not. In some instances a can of food may well be safe several years after that sell by date has passed. The general rule of thumb in the industry is that canned goods are ok for up to two years after the sell by date, provided of course that safe food handling practices have been followed.

Under most food laws, a retailer must sell or dispose of sell by dated food on or before that date listed on the can. If you buy a can of peas dated sell by 10 Dec 2009, that doesn’t mean you must use it before that date or throw it out. These sell by dates simply tell the retailer when the food should be sold by. In many cases the retailer is still free to donate that expired food to a food bank or soup kitchen.

The best if used by date simply means that for optimum quality and nutritional value, the food should be prepared and consumed by that date. The use by date means the same thing, it’s just worded different because some lawyer needed to make some extra bucks. Those gobbledygook numbers are merely a manufacturer’s way of having a unique code for their cans, and these can be the hardest to decode. These are usually used on product that can have a long safety life if stored properly.

Some canned goods can have a safety zone of decades after the sell by date, such as Dinty Moore Beef Stew. According to their faq section, The processing techniques utilized by Hormel Foods makes the canned product safe for use indefinitely if the product seal remains intact, unbroken and securely attached to a can that has been well maintained… That’s a good long time, but they also recommend that the product be used within 2 to 3 years after the sell by date.

Other manufacturers have differing standards so you should take the time to do some research on your food dates to learn how to read the codes, and see what the manufacturer suggests for storage life capabilities.

What constitutes safe storage?

Safe storage means that your food needs to be kept under controlled temperatures, general guidelines call for a range of a low around 60˚F to 70˚F for best results. I prefer the low 60s range myself. The area must be kept clean, and free of insects and rodents. It also must be dry, with a low humidity level. Your canned goods also need to be kept out of direct sunlight. Never place your canned good directly on a concrete floor, even if they are in a case pack. At the very least they should be on a pallet, although sturdy shelving is the best place to put them.

Your canned goods should be rotated for best performance, and it also helps to write the date of purchase on the top of the can with a magic marker. Keep the cans fronted, or to the leading edge of the shelf, and make sure there is room between the top of the can and the bottom of the shelf above to make it easier to place newly purchased cans.

Place the larger, heavier cans on the lower shelves so the storage unit doesn’t become too top heavy and prone to toppling during an earthquake. Ideally, any bagged and boxed mixes and powders should go on the top shelves.

Also, along with your pantry goods should be a portable stove and a kit of pots and pans for cooking your canned goods in an emergency. The smart way to store is to build a bomb shelter/room, and utilize that as your emergency shelter as well as your pantry/storage room. You can also keep water, blankets, flashlights and candles along with any other supplies you may need for your area. Camp cots and/or sleeping mats and bags are something almost everyone I have discussed this with seems to leave out for some reason. If you have a concrete floor, you are much better off comfort wise with the camp cots, by the way.

Canned goods should be used as your first line of supply in any emergency situation, with long term foods stored as a worst case scenario food source. That being the case you need to take just as much care with these products as you would any other food product. And they don’t need to be such a worry, either. Just remember that the sell by date doesn’t mean the content is no good after that date, and that canned goods do eventually degrade to some extent, but not for several years after that sell by date.

Discard any cans that have corrosion on them, or that have become severely dented by dropping on the floor. Also discard any canned goods that spurt when opened or that may have an off odor coming from them when opening. These are signs of contamination. Most cans will “exhale” when opening, but if the hiss seems unusually loud, or long it could also mean the food is contaminated. Examine it carefully, and discard if in doubt.

As an added suggestion, always wipe off the top of the can with a clean damp rag to make sure there are no contaminants that may get into the food when opening.