Zap! Protecting Your Practice Against an Electrical Blackout

Gregory A. Hood, MD


August 05, 2019

Imagine you're in an exam room with a patient. You start typing into your electronic health record (EHR), and everything goes pitch black. The computer, room, and hall lights, everything, suddenly have no power.

Such a blackout occurred recently in New York City, when large swaths of the city were plunged into darkness for as long as 5 hours in some areas.

Blackouts often occur for a short time span in towns across the country for mundane reasons. For example, in 2017 alone, 3500 blackouts were reported across the United States—earning the USA the status as the least reliable electrical grid among developed nations.[1]

Over the past 14 years, my practice in Kentucky has suffered two small power outages from lightning storms, called electromagnetic pulses (EMPs). An EMP is a burst of electromagnetic energy, potentially one of enormous potency.

An EMP's electrical discharge can cause substantial damage to the power grid as well as sensitive electronics, whether they are plugged into the grid at that moment of the discharge or not. EMPs are also generated by a very close lightning strike conducted through wiring, or a suddenly fluctuating magnetic field, such as from solar storms, among other causes, including the remote change of a nuclear discharge.

The first one to affect my office destroyed our phone system and caused other damage. We upgraded our surge protection system's capacity. This proved helpful during the next lightning strike, which was a more direct hit. Fortunately, we had only a temporary loss of services with that one. Had we not upgraded our defenses, we well might have suffered significant damage to our more recently implemented EHR.

A power outage can begin in many ways. They range from the simple and mundane to the unusual, and even the devastating. We have an electrical grid that is aging and has not been modernized. Depending on many power lines and power plants that were built shortly after World War II,[2] it has vulnerabilities that can be exposed during the increase in unstable and extreme weather events which seem to be afflicting our nation.

Seven Ways to Protect Yourself and Your Patients

There are, however, ways in which you can prepare and help yourself in the event of an EMP.

1. Make an effort to block electromagnetic radiation. Wonder why your cell phone won't work in some buildings? It's because arrangements of conducting material in your building's walls can block incoming electromagnetic radiation wavelengths. Adding such material could actually help you block electromagnetic radiation wavelengths. You can build boxes for such protection, called "Faraday cages,"[3] which are enclosures used to block electromagnetic fields. Within these enclosures, you can store data backups on external hard drives. A copy of your data may thereby remain intact, to restore after the event.

2. Keep some operating money in actual, well-secured cash. I know this is very difficult, especially with rising overheads and narrowing margins, but if there is a national or global EMP, then financial records worldwide could be devastated. Having some cash on hand can help you, and allow you to help your employees, in the short term.

Don't think of this as a resource to fund the entire, normal operations of the practice. Rather, remember the scene in It's a Wonderful Life when there is a run on the savings and loan, where everyone comes together to take just what they need in order to keep everyone going. Depending on the practice size and number of staff, a few thousand dollars could arrange for necessary services/support and can help you, and allow you to help your employees, in the short term.

3. Consider backup and alternative power sources for your office. After Hurricanes Katrina, Harvey, and Irma, several offices tried to serve their patients, but without power, rendering care was that much more difficult. Planning for this can be more difficult for an EMP event than a hurricane because several types of backup power generation can contain EMP-sensitive circuits. Faraday cages can protect them while stored and some low-tech solutions can provide some electric power, which is better than nothing.

4. Maintain an adequate inventory just in case. Be sure to have a stock of medical equipment, supplies, and medications to practice your usual specialty in an emergency. Production and delivery of such materials is quite likely to be disrupted and uneven after a major EMP event, potentially for an extended period.

5. Preserve critical paper documents. Maintain print copies of major documents, such as leases, employment agreements, and contracts. It is also appropriate to preserve in print some manuals that outline usual office policies and guidelines for how work is to be performed should electronics not be available, whether because of ordinary blackout or more extraordinary events.

You might also want to keep some textbooks and reference materials in print form. …As a profession, we've become accustomed to having all the answers at our fingertips.

You might also want to keep some textbooks and reference materials in print form. You can find recent print versions inexpensively through online booksellers. As a profession, we've become accustomed to having all the answers at our fingertips.

It's rare to find a problem to which I can't quickly look up the answer on or other online searches. However, there are core resources in my internal medicine practice, such as Harrison's Internal Medicine, and key books in orthopedics, dermatology, primary care, and procedural references that, even on an ordinary day, I may pull and refer to instead of going online. For some of these, I do so out of familiarity, and for others, it's because they contain resources, diagrams, and charts that are no longer readily available online.

6. Consider the quality of your surge suppressors. Suppressors are constructed commercially to variable degrees of robustness and integrity. They are also designed to protect against slower-building charges, such as from lightning or a blown transformer. A natural EMP, or that of a high-altitude nuclear detonation, may surge with a peak energy and duration of energy so severe and so short that the surge suppressor may not have time to react.

7. Keep consistent with your hardware. Standardize the computers and electronic devices you use so that the interchangeability of undamaged or spare parts will be compatible in salvaging recoverable devices. Consider that the primary source of replacement parts may be overseas and effectively unobtainable for some time. Consider retaining recently replaced or depreciated hardware in a comparatively EMP-insulated area to use in the event primary equipment is unusable, or their parts are salvageable.

Although the most likely threats to our electrical grids may come from lightning, solar storms, a solar coronal mass ejection, or other natural sources, there could potentially be national threats from political sources. Uncertain relationships with such countries as North Korea and Iran, for example, have long been considered a threat for electrical grid damage in the United States, from hacking, sabotage, or even an electromagnetic pulse from an atmospheric nuclear discharge.[4]

Is possibility of widespread outage preposterous? The insurance giant Lloyd's of London apparently doesn't think so. "Business Blackout," a joint report by Lloyd's and the University of Cambridge's Centre for Risk Studies,[5] considers the insurance implications of a cyberattack on the US power grid.

This report publishes, for the first time, the impacts of this sort of attack using the hypothetical scenario of an electricity blackout that plunges 15 US states, including New York City and Washington, DC, into darkness and leaves 93 million people without power. The scenario, while improbable, is technologically possible and is assessed to be within the benchmark return period of 1:200 against which insurers must be resilient.[5]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: