As personal bpdyguards to Chairman Stahl, HAZMAT Troopers are given the right weapons needed to keep the Chairman safe. They can survive with their heavy armor longer than any other Helghast soldier and carry Petrusite weapons with them. Although they appear in many cutscenes throughout the game extracting petrisute, they are rarely seen in the actual game and only a handful of them are actually seen fighting in game. Only a few are scattered throughout the Stahl Arms Deep South Facility, they are one of the final enemies during the last mission of the campaign and are seen protecting Stahl in space. They also appear in the later half of Killzone 3 as they are seen acting as support troopsers helping the advancemnt of Helghast Troops and to repel human forces.
HAZMAT Troopers are given the most advanced and state of the art weapons and grea they need. They have VC5-Arc Rifles and heavy duty armor to protect themselves whenever they're in combat. HAZMAT Troopers are also seen using their armor to extract irradiated petrusite from the bombed-out ruins of Helghan.