There are two different types of nuclear devices in Empire: fission bombs, fusion bombs. Both fission and fusion bombs perform similarly, with fusion bombs giving more bang for the buck.
In general, the only way to avoid damage by a nuclear detonation is to avoid the area prior to and during actual detonation. Hardening missiles (in silos) is the only exception, and even that cannot protect from a direct hit by the larger nuclear devices.
The details of the nuclear devices present in Empire can be seen using the show command. The meaning of the fields are as follows:
The nukes name.
The amount of lcm needed to build the nuke
The amount of hcm needed to build the nuke
The amount of crude oil required to build it.
The number of radioactive products required to build it.
The avail (work) required to build the nuke.
The minimum tech level required to construct the nuke.
The minimum research level required to construct the nuke.
The cost of the nuke to construct.
The blast type of the nuke
The damage rating of the nuke
the weight of the warhead, limiting missile and plane nuclear device carrying capacity.
Special abilties, if any
The abilities are as follows:
Creates much more severe nuclear fallout.
As a guide (these numbers are subject to change):
[##:##] Command : show nuke build
Printing for tech level '300'
lcm hcm oil rad avail tech res $
10kt fission 50 50 25 70 49 280 0 $ 10000
15kt fission 50 50 25 80 51 290 0 $ 15000
50kt fission 60 60 30 90 60 300 0 $ 25000
[##:##] Command : show nuke capab
Printing for tech level '300'
blst dam lbs tech res $ abilities
10kt fission 3 70 4 280 0 $ 10000
15kt fission 3 90 5 290 0 $ 15000
50kt fission 3 100 6 300 0 $ 25000
The larger the megatonnage, the more damage done by the weapon. Effects (as in the real world) can only be determined by experimentation, although research suggests that radioactivity left behind by nuclear detonations may have lasting effects.
See also : launch , fly , build , transport , show , Planes , Nukes , Fallout