Electromagnetic pulses are not atop the list of the average person’s potential disasters, but the risk of one happening does exist. These can occur due to solar flares, natural phenomena, or man-made devices such as nuclear bombs and pulse-power.
A high altitude nuclear-based EMP (HEMP) has three waveforms, which are referenced as E1, E2, and E3. The first is very fast – from a nanosecond to a few seconds – and is the one that causes much immediate disruption. It works strongly on general systems including electrical and computer, sensors, and electrical controls. E2 lasts somewhat longer but has less amplitude and mostly works on long lines; its damage is similar to that of lightning strikes. E3 lasts much longer and affects communication lines and connected equipment; these effects are like the effects of solar geomagnetic disturbances.
The government has examined the risk and ways to limit the damage. They have put things into place to watch for the potential from other countries; they have also discussed adding shielding to critical components to aid in resisting EMP. Testing and research continues to assess the danger and find ways to handle it if it happens. The President of the United States signed an Executive Order in March 2019 for the purpose of being prepared in the case of an EMP, regardless of its source.
Understanding the Danger
The personal danger will depend, to some degree, on the source of the EMP. If it is from a geomagnetic disturbance such as solar flares, bodily harm is very unlikely. If the source is nuclear, then radiation is always a factor that must be considered. Man-made devices are usually nuclear in nature. Natural phenomena such as lightning strikes can cause bodily harm if one is too near the strike or is struck.
However, extended exposure to EMP or a very strong one has the potential to cause some issues such as cellular mutations, internal burns, nervous system damage, brain damage, or problems with thinking or memory, which are usually temporary. However, these effects are not common.
According to ready.gov, there are several hazards from nuclear EMPs, which come from nuclear weapons.A very bright light can cause temporary blindness. The wave from the blast, especially a land-based blast, can injure or kill people and cause damage to buildings and other structures for some distance. The radiation can cause sickness. Fire can occur and cause related damage, injuries, or death. The fallout, which is radioactive, can include debris that rains down from a high-altitude blast or that was kicked into the air from a land-based blast.
The Hawaiian government states that proximity can be less of an injury risk if the people will go indoors, stay there, and stay tuned to information available. Indoors means a sturdy structure that is unlikely to be seriously damaged by a blast. This is usually a concrete structure, possibly underground. Many radio stations are likely to be sharing information, if possible.
What to Do Before It Happens
Being prepared is important. Some EMPs happen without prior warning, so there is no time to get prepared. Even those that can be seen before they happen – such as solar flares – have a limited time before the effects are felt. Therefore, getting prepared must happen during times when there is no imminent threat.
The recommendations include:
- Have two weeks’ worth of supplies – food, water, medication – stored. Remember to check it regularly and rotate the stock to keep it fresh.
- Keep your gas tank as full as possible, in cases when it may be necessary to evacuate. Waiting to gas up until an evacuation is called may find gas stations closed or unable to pump gas if electric is unavailable. If possible, plan to only take one vehicle, to help lessen potential traffic issues. If you do not own a car, pre-plan with a friend or neighbor a way to evacuate if necessary.
- Know first aid and how to use a fire extinguisher, as well as where it is stored.
- Have emergency kits at home, at work, and in the car. The home kit should have the food and water and emergency supplies (including medication). The work kit should be easy to carry, contain food and water, and should be accompanied by comfortable shoes in which you could walk long distances. The car kit should have food and water, first aid, jumper cables, flares, and other necessary supplies.
- There are some areas that tend to be a higher risk of a nuclear attack. These include government locations, military locations, large transportation, communication, manufacturing, industrial, financial, electrical, and chemical locations, primarily. Concerned citizens could consider relocating to a less risky location or be sure to be fully prepared in case something happens.
What to Do as It Is Happening
- Blast shelters will protect from the concussion of a blast, while fallout shelters just need to be safe with thick enough roof and walls to keep the radiation from reading the interior. Ideally, this shelter would be underground. If there is advance warning, get inside immediately!
- If shelter is not immediately available, take cover anywhere possible, and do not look at the blast: it can blind you. If no cover is available, lie down on the ground as flat as possible and cover your head. A distant blast can take nearly a minute to reach you. Find shelter as soon as possible, even if you are some distance away, because fallout can ride the wind. It is important to be inside before the fallout reaches you.
- Tune in to news, if possible. Follow official instructions that reach you. Stay inside until it is declared safe to leave. The CDC offers more information about sheltering.
What to Do After It Happens
If you were not inside before the blast, your clothing is potentially contaminated with radioactive material. Remove it as soon as possible and wash with soap and water any part that was not covered, including hair. Do the same for any pets that were outside, as well.
Do not eat or drink anything that was outside, as it may be contaminated.
If you have been injured, or are sick, authorities will tell you when it is safe to exit and where to go for treatment.
FEMA has an information sheet that explains how to be prepared for a nuclear explosion and the related dangers.
If the EMP was not related to a nuclear blast, continuing life will be less problematic. If the electricity is knocked out, it may cause a change in life, but it is likely to be relatively short-lived. The Department of Energy has an Action Plan in the case of a situation occurring. They are in the process of reducing vulnerabilities in order to have a less detrimental result in the case of an EMP happening.