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 of overpressure
According to an article in the journal Toxicological Sciences,
"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."
|10 pounds per square inch (69 kPa)||
|4 pounds per square inch (28 kPa)||
|2 pounds per square inch (14 kPa)||
Overpressure calculation (explosive)
Overpressure is determined using "Weibull's formula":
- 2410 is a constant based on 1 bar (100 kPa; 15 psi)
- = net explosive mass calculated using all explosive materials and their relative effectiveness
- = volume of given area (primarily used to determine volume within an enclosed space)
- "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
- Pavlus, John (March 4, 2010). "Real-life Hurt Locker: how bomb-proof suits work".
- Fool Me Twice (documentary film). Event occurs at 1h 6m. Retrieved 2007-12-26.