Overpressure

Quality 0.50 · 2 views · Updated 2 months ago

Pressure due to a shockwave

title: "Overpressure" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["pressure", "explosives", "shock-waves"] description: "Pressure due to a shockwave" topic_path: "general/pressure" source: "https://en.wikipedia.org/wiki/Overpressure" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Pressure due to a shockwave ::

Overpressure (or blast overpressure) is the pressure caused by a shock wave over and above normal atmospheric pressure. The shock wave may be caused by sonic boom or by explosion, and the resulting overpressure receives particular attention when measuring the effects of nuclear weapons or thermobaric bombs.

Effects

According to an article in the journal Toxicological Sciences,

::quote Blast overpressure (BOP), also known as high energy impulse noise, is a damaging outcome of explosive detonations and firing of weapons. Exposure to BOP shock waves alone results in injury predominantly to the hollow organ systems such as auditory, respiratory, and gastrointestinal systems."Pulmonary Biochemical and Histological Alterations after Repeated Low-Level Blast Overpressure Exposures", Nabil M. Elsayed, and Nikolai V. Gorbunov, Toxicological Sciences, 2007 95(1):289-296, online version 2006, http://toxsci.oxfordjournals.org/cgi/content/abstract/95/1/289 ::

An EOD suit worn by bomb disposal experts can protect against the effects of BOP.

::data[format=table] | Overpressure psi (kPa; bar) | Effect on buildings and people within | |---|---| | 1 psi | | | | 2 psi | | | | 3 psi | | | | 5 psi | | | | 10 psi | | | | 20 psi | | ::

The above table details the effects of overpressure on the human body in a building affected by a blast of overpressure waves, as clarified later in the journal.

According to documents released by the United States Military Defense Technical Information Center (DTIC), ::quote

::

It is important to note that this is for "Instantaneous peak pressure" while the preceding table is for long duration pressure.

Calculation for an enclosed space

Overpressure in an enclosed space is determined using "Weibull's formula":

\Delta p = 22.5 \left( {m \over V} \right)^{0.72} \text{bars}

where:

  • 22.5 is a constant based on experimentation
  • m, = (kilograms) net explosive mass calculated using all explosive materials and their relative effectiveness
  • V, = (cubic meters) volume of given area (primarily used to determine volume within an enclosed space)

References

References

  1. Pavlus, John. (March 4, 2010). "Real-life Hurt Locker: how bomb-proof suits work".
  2. "Effects of blast pressure on the human body".
  3. "Blast Effects of Bomb Explosives".
  4. (1968). "Pressures Recorded in Partially Closed Chambers at Explosion of TNT Charges". Annals of the New York Academy of Sciences.
  5. "Laboratory barricade".

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::

pressureexplosivesshock-waves