Hazmat Suit Leggings are an armor piece added by IndustrialCraft 2 that protects the player against environmental dangers, such as fire, lava and radiation. The full Hazmat set will protect against most environmental dangers.
When wearing the full Hazmat set, the player is protected from most environmental damage (radiation, fire, fall damage..), except potion effects - e.g. poison and hunger. The set is very weak, though, and will drain durability very quickly. When the armor is out of durability, it will not break, but it won't protect from damage anymore.
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