Blast Map
Visualize nuclear blast radius effects for selected weapon yields. Radii are approximate and scaled for comparison.
1.0x
| Zone | Approx. Radius |
|---|---|
| Fireball | 4 km |
| Air Blast (5 psi) | 24 km |
| Thermal Radiation | 50 km |
| Initial Radiation | 30 km |
Nuclear Blast Effect Zones Explained
A nuclear detonation produces several distinct concentric zones of destruction. Each zone represents a different physical mechanism with different effects on people and structures.
Fireball
Total vaporisation. Temperatures reach millions of °C. Nothing survives within this radius.
Heavy Blast
~20 psi overpressure. Reinforced concrete structures collapse. Near-100% fatality rate.
Moderate Blast
~5 psi overpressure. Residential buildings destroyed. Most people killed or seriously injured.
Light Blast
~1 psi overpressure. Window shattering, structural damage. Injuries from flying debris.
Thermal Radiation
Severe burns to exposed skin. Fires ignited. Effects blocked by buildings and terrain.
Radiation / Fallout
Ionising radiation dose sufficient to cause acute radiation syndrome in unprotected individuals.
Yield Reference — Historical & Modern Weapons
Weapon yield is measured in kilotons (kt) or megatons (Mt) of TNT equivalent. To put scale into context:
| Weapon / Event | Yield | Context |
|---|---|---|
| Little Boy (Hiroshima) | 15 kt | First nuclear weapon used in war, 1945 |
| Fat Man (Nagasaki) | 21 kt | Second nuclear weapon used in war, 1945 |
| Typical modern warhead | 100–500 kt | Current US/Russia ICBM warheads |
| Tsar Bomba | 50 Mt | Largest nuclear device ever detonated (USSR, 1961) |
| Hiroshima vs Tsar Bomba | 3,300× | Tsar Bomba was 3,300× larger than Hiroshima |
Frequently Asked Questions
What does this nuclear blast map show?
The map visualises the four main zones of destruction from a nuclear detonation: the fireball (total vaporisation), the heavy blast zone (reinforced buildings destroyed), the moderate blast zone (residential buildings destroyed), and the thermal radiation zone (third-degree burns). Sizes are calculated from declassified nuclear weapons effects research.
What is the fireball zone?
The fireball is the initial superheated plasma sphere that reaches millions of degrees. Everything within this radius is instantly vaporised. For a 15-kiloton bomb (Hiroshima-scale), the fireball radius is roughly 200–300 metres.
What is the air blast zone?
The air blast is the pressure wave expanding outward from the detonation. The heavy blast zone (overpressure ~20 psi) destroys reinforced concrete buildings. The moderate blast zone (~5 psi) collapses residential structures. Further out, the light blast zone (~1 psi) shatters windows and causes injuries from flying glass.
What is thermal radiation and how far does it reach?
Thermal radiation is the intense heat flash emitted in the first seconds. It causes fires and severe burns at distances far beyond the blast wave. A 1-megaton detonation can cause third-degree burns up to 10km away on a clear day. Thermal effects are blocked by buildings, hills, and even clothing.
Is this tool accurate?
The tool uses established nuclear effects models (based on research like the Glasstone and Dolan “Effects of Nuclear Weapons” reference). It is a reasonable educational approximation — actual effects vary with altitude, terrain, weather, and building density.
Is this tool for educational use only?
Yes. This is a public awareness and educational visualiser, similar to tools produced by academic institutions and nonproliferation organisations. Understanding nuclear weapon effects is widely considered important for informed public discourse on nuclear policy and deterrence.