Chagai-I

Test devicePakistanLayered fission–fusion

No freely licensed photo of this device yet.

Yield · TNT equivalent9–40 kt

Key specs

Country: Pakistan
Design: Layered fission–fusion
Type: Test device
Number built: 5

Overview

Pakistan’s first nuclear tests: five devices fired simultaneously in a tunnel under the Ras Koh Hills on 28 May 1998, two weeks after India’s Shakti tests. Pakistan claimed a combined yield of up to 40 kt with a boosted main device; independent seismic estimates are about 9–12 kt.

Effect radii: estimates

Calculated for 40 kt

Fireball, maximum radius: ≈ 270 m
Initial radiation, 500 rem (5 Sv): ≈ 1.7 km
Blast 5 psi: most buildings collapse: ≈ 2.4 km
Thermal: third-degree burns: ≈ 3 km
Blast 1 psi: windows shatter: ≈ 7.5 km

Estimated ground ranges for an air burst at the optimum height over flat, open ground, computed from the yield with standard scaling laws. These are not measurements: real effects depend on the height of burst, terrain, buildings and weather.

Formulas from: Glasstone & Dolan, The Effects of Nuclear Weapons (1977), chapter II; Carey Sublette, Nuclear Weapons FAQ, section 5

Tests and use

Date	Event	Site	Yield
May 28, 1998	Chagai-I	Ras Koh Hills, Chagai, Pakistan	40 kt

Sources

Chagai-I, Wikipedia