Car Bombs vs. Human Beings explains the realities of this terrorist weapon:
Most of us have only seen explosions in movies where slow-motion photography or the use of low velocity explosions with lots of smoke and flame create spectacular, lingering visual effects. Real bombs, using a high order of explosives, go off in a millisecond flash doing huge damage in a literal instant. There is little for the eye to linger upon. One moment everything is normal. Then a supersonic boom. Then destruction.
[...]
The human body contains two principal air-filled spaces — the lungs and the nasal cavity and attached sinuses. A human subjected to a bomb blast wave instantly has hundreds and perhaps thousands psi of pressure pushing on these cavities. A mere 15 psi above normal is considered the threshold for possible lung injury, so imagine what happens to those near the epicenter of a bomb blast.The chest caves in. The lungs inside it are compressed violently in on themselves — so violently that the entire network of pulmonary vessels connecting them to the heart and the rest of the body are sheared off.
When the instant of blast overpressure passes, the lungs suddenly re-expand, like a crushed rubber ball rebounding in the hand of a strong man. But now they are filled with a huge volume of blood, blood that should be flowing to the heart and other parts of the body.
Blood that would normally return to the heart through the left ventrical has now overwhelmed the lungs. No blood in the left ventrical equals no blood in the heart equals no pulmonary output to the body. Blood pressure — zero. The body is instantly starved.
Up above, in the skull, at the same instant, the overpressure works in another way. The nasal and sinus cavities implode. That part of the skull called the cribiform plate ruptures, snaps and may be thrust upward into the base of the brain.
Kind of academic, isn’t it? You can die so many ways in the space of a few seconds in a bomb blast.