Editing Nuclear electromagnetic pulse (section)

==Effects==
An energetic EMP can temporarily upset or permanently damage electronic equipment by generating high voltage and high current surges; semiconductor components are particularly at risk. The effects of damage can range from imperceptible to the eye, to devices blowing apart. Cables, even if short, can act as antennas to transmit pulse energy to the equipment.<ref name="metaR320"/>

===Vacuum tube vs. solid-state electronics===
Older, [[vacuum tube]] (valve)-based equipment is generally much less vulnerable to nuclear EMP than [[solid-state electronics|solid-state]] equipment, which is much more susceptible to damage by large, brief voltage and current surges. [[Soviet]] [[Cold War]]-era military aircraft often had [[avionics]] based on vacuum tubes because solid-state capabilities were limited and vacuum-tube gear was believed to be more likely to survive.<ref name="science"/>

Other components in vacuum tube circuitry can be damaged by EMP. Vacuum tube equipment was damaged in the 1962 testing.<ref name="euroem"/> The solid-state [[PRC-77]] [[VHF]] manpackable two-way radio survived extensive EMP testing.<ref name="PRC77">Seregelyi, J.S, et al. [http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA266412&Location=U2&doc=GetTRDoc.pdf Report ADA266412 "EMP Hardening Investigation of the PRC-77 Radio Set] {{Webarchive|url=https://web.archive.org/web/20111112122352/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA266412&Location=U2&doc=GetTRDoc.pdf |date=2011-11-12}}" Retrieved 2009-25-11</ref> The earlier PRC-25, nearly identical except for a vacuum tube final amplification stage, was tested in EMP simulators, but was not certified to remain fully functional.{{citation needed|date=August 2016}}

===Electronics in operation vs. inactive===
Equipment that is running at the time of an EMP is more vulnerable. Even a low-energy pulse has access to the power source, and all parts of the system are illuminated by the pulse. For example, a high-current arcing path may be created across the power supply, burning out some device along that path. Such effects are hard to predict and require testing to assess potential vulnerabilities.<ref name="metaR320">
{{cite report |last1=Savage |first1=Edward |last2=Gilbert |first2=James |last3=Radasky |first3=William |docket=Meta-R-320 |title=The Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP) and Its Impact on the U.S. Power Grid |section=Appendix: E1 HEMP Myths |date=January 2010 |publisher=Metatech Corporation for Oak Ridge National Laboratories |df=dmy-all |url=https://www.ferc.gov/industries/electric/indus-act/reliability/cybersecurity/ferc_meta-r-320.pdf |access-date=2017-09-08 |url-status=dead |archive-url=https://web.archive.org/web/20170520145500/https://www.ferc.gov/industries/electric/indus-act/reliability/cybersecurity/ferc_meta-r-320.pdf |archive-date=2017-05-20}}</ref>

===On aircraft===
Many nuclear detonations have taken place using [[aerial bomb]]s. The [[B-29]] aircraft that delivered the nuclear weapons at [[Hiroshima]] and [[Nagasaki]] did not lose power from electrical damage, because [[electron]]s (ejected from the air by gamma rays) are stopped quickly in normal air for bursts below roughly {{convert|10|km|ft||}}, so they are not significantly deflected by the Earth's magnetic field.<ref name="Glasstone_1977">{{cite book |last1=Glasstone |first1=Samuel |author-link1=Samuel Glasstone |last2=Dolan |first2=Philip J. |author-link2=Philip J. Dolan |date=1977 |title=The Effects of Nuclear Weapons |chapter=XI: The Electromagnetic Pulse and its Effect |publisher=[[United States Department of Defense]] and [[United States Department of Energy]] |oclc=1086574022 |ol=OL10450457M |via=[[Google Books]] |df=dmy-all |isbn=978-0318203690 |url={{Google books|KOM8AAAAIAAJ|plainurl=yes}}}}</ref>{{rp|page=517}}

If the aircraft carrying the [[Hiroshima]] and [[Nagasaki]] bombs had been within the intense nuclear radiation zone when the bombs exploded over those cities, then they would have suffered effects from the [[photoinduced charge separation|charge separation]] (radial) EMP. But this only occurs within the severe blast radius for detonations below about {{convert|10|km|ft|order=flip}} altitude.{{citation needed|date=August 2016}}

During [[Operation Fishbowl]], EMP disruptions were suffered aboard a [[KC-135]] photographic aircraft flying {{convert|300|km|abbr=on}} from the {{convert|410|ktonTNT|abbr=on}} detonations at {{convert|48|and|95|km|ft|abbr=on}} burst altitudes.<ref name="glasstone.blogspot.com">{{cite web |title=EMP radiation from nuclear space bursts in 1962 |last1=Glasstone |first1=Samuel |author-link1=Samuel Glasstone |date=2006-03-28 |website=Glasstone's errors in The Effects of Nuclear Weapons, and the strategic implication for deterrence |language=en |df=dmy-all |url=http://glasstone.blogspot.com/2006/03/emp-radiation-from-nuclear-space.html |access-date=2022-08-10 |url-status=live |archive-url=https://web.archive.org/web/20220811022617/https://glasstone.blogspot.com/2006/03/emp-radiation-from-nuclear-space.html?m=1 |archive-date=2022-08-11 |quote=Subsequent tests with lower yield devices [410 kt ''Kingfish'' at 95 km altitude, 410 kt ''Bluegill'' at 48 km altitude, and 7 kt ''Checkmate'' at 147 km] produced electronic upsets on an instrumentation aircraft [presumably the KC-135 that filmed the tests from above the clouds?] that was approximately 300 kilometers away from the detonations.}}<!-- blog source was https://fas.org/spp/starwars/congress/1997_h/h970716u.htm &ndash; testimony to 1997 U.S. Congressional Hearings, Dr. George W. Ullrich, the Deputy Director of the U.S. Department of Defense's Defense Special Weapons Agency --></ref> The vital electronics were less sophisticated than today's and the aircraft was able to land safely.{{citation needed|date=August 2016}}

Modern aircraft are heavily reliant on solid-state electronics which are very susceptible to EMP blasts. Therefore, airline authorities are creating high intensity radiated fields (HIRF) requirements for new airplanes to help prevent the chance of crashes caused by EMPs or electromagnetic interference (EMI).<ref>{{cite book |title=Electromagnetic Shielding and Corrosion Protection for Aerospace Vehicles |year=2007 |language=en |last1=Gooch |first1=Jan W. |last2=Daher |first2=John K. |isbn=978-0-387-46094-9 |doi=10.1007/978-0-387-46096-3 |url=https://link.springer.com/book/10.1007/978-0-387-46096-3}}</ref> To do this all parts of the airplane must be conductive. This is the main shield from EMP blasts as long as there are no holes for the waves to penetrate into the interior of the airplane. Also, insulating some of the main computers inside the plane adds an extra layer of protection from EMP blasts.{{citation needed|date=February 2024}}

===On cars===
An EMP would probably not affect most cars, despite modern cars' heavy use of electronics, because cars' electronic circuits and cabling are likely too short to be affected. In addition, cars' metallic frames provide some protection. However, even a small percentage of cars breaking down due to an electronic malfunction would cause traffic jams.<ref name="metaR320"/>

===On small electronics===
An EMP has a smaller effect on shorter lengths of an electrical conductor. Other factors affect the vulnerability of electronics as well, so no hard cutoff length determines whether some piece of equipment will survive. However, small electronic devices, such as wristwatches and cell phones, would most likely withstand an EMP.<ref name="metaR320"/>

===On humans and animals===
Though electric potential difference can accumulate in electrical conductors after an EMP, it will generally not flow out into human or animal bodies, and thus contact is safe.<ref name="metaR320"/>

EMPs of sufficient magnitude and length have the potential to affect the human body. Possible side effects include cellular mutations, nervous system damages, internal burns, brain damage, and temporary problems with thinking and memory.<ref>{{cite web |last1=Walter |first1=John |title=How an EMP Attack Would Affect Humans |website=Super Prepper |language=en-US |df=dmy-all |url=https://www.superprepper.com/emp-effects-on-humans/ |access-date=2022-08-11 |url-status=live |archive-url=https://web.archive.org/web/20211029222217/https://www.superprepper.com/emp-effects-on-humans/ |archive-date=2021-10-29}}</ref> However, this would be in extreme cases like being near the center of the blast and being exposed to a large amount of radiation and EMP waves.

A study found that exposure to 200–400 pulses of EMP caused the leaking of vessels in the brain,<ref>{{cite journal |last1=Ding |first1=Gui-Rong |last2=Li |first2=Kang-Chu |last3=Wang |first3=Xiao-Wu |last4=Zhou |first4=Yong-Chun |last5=Qiu |first5=Lian-Bo |last6=Tan |first6=Juan |last7=Xu |first7=Sheng-Long |last8=Guo |first8=Guo-Zhen |date=June 2009 |title=Effect of electromagnetic pulse exposure on brain micro vascular permeability in rats |journal=Biomedical and Environmental Sciences |volume=22 |issue=3 |pages=265–268 |issn=0895-3988 |pmid=19725471 |doi=10.1016/S0895-3988(09)60055-6|bibcode=2009BioES..22..265D }}</ref> leakage that has been linked to small problems with thinking and memory recollection. These effects could last up to 12 hours after the exposure. Due to the long exposure time needed to see any of these effects it is unlikely that anyone would see these effects even if exposed for a small period of time. Also, the human body will see little effect as signals are passed chemically and not electrically making it hard to be affected by EMP waves.{{citation needed|date=February 2024}}

=== Indirect effects on agriculture ===
In addition to these direct effects, it has also been estimated that the disruption caused by the NEMP would have large negative effects on agriculture, due to the disruption of supply chains for agricultural inputs like fertilizers and pesticides. This could reduce yields in highly industrialized agricultural regions like Central Europe by up to 75 %.<ref>{{cite journal |last1=Moersdorf |first1=Jessica |last2=Rivers |first2=Morgan |last3=Denkenberger |first3=David |last4=Breuer |first4=Lutz |last5=Jehn |first5=Florian Ulrich |title=The Fragile State of Industrial Agriculture: Estimating Crop Yield Reductions in a Global Catastrophic Infrastructure Loss Scenario |journal=Global Challenges |date=January 2024 |volume=8 |issue=1 |doi=10.1002/gch2.202300206|pmc=10784200 }}</ref>