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CBRN module

From Halopedia, the Halo wiki

The CBRN module (right) with a HUL (left).

The CBRN module, short for the Chemical, Biological, Radiological and Nuclear module, is an external attachment for several MJOLNIR Mark V and GEN3 helmets.[1][2]


The CBRN module is employed for operations in hazard zones, wherein chemical, biological, radiological and nuclear threats are present.[3]


The CBRN module has been observed to be compatible with the following helmets:


The CBRN module has three observed variants, each with its own distinct physical appearance.

Standard variant[edit]

The standard variant is single-piece rebreather covering the "mouth" area of the given helmet.

EOD-style variant[edit]

The EOD-style variant of the CBRN module is a pair of filter attachments on either side of the helmet. It is employed on the standard Mark V EOD-class Mjolnir helmet, but it could be removed for other helmet attachments.[9]

AKIS-style variant[edit]

AKIS-style variant was developed in parallel to the AKIS helmet, and has only been observed as compatible to the AKIS helmet.[10]


The CBRN module and its variants serve as cosmetics and have no impact on gameplay.

Halo: Reach[edit]

The first two variants of the CBRN module are available as attachments on several helmets in the armor permutations of Halo: Reach. The device is priced at different levels of Credits, depending on the base helmets. In Halo: The Master Chief Collection, the same CBRN-attached helmets are unlockable in Season 1: Noble, while the AKIS-style variant added in Season 5: Anvil.

Halo 5: Guardians[edit]

The CBRN module is featured on the EOD GEN1 helmet, which is one of the helmets that could be acquired through the Classic Helmet REQ Pack in Halo 5: Guardians .

Halo Infinite[edit]

A variant of the CBRN module will be available on the Commando helmet in Halo Infinite.[2]

Production notes[edit]

"CBRN" stands for chemical, biological, radiological, and nuclear, and is pronounced "C-BURN". It is the same abbreviation used in real life, hence its association with the HAZOP armor permutation.


List of appearances[edit]


  1. ^ Halo: Reach - Armory
  2. ^ a b Xbox, Halo Infinite (Retrieved on Jun 14, 2021) [archive]
  3. ^ a b c d Halo: Reach - Armory: AKIS, CQC, and GUNGNIR - CBRN Helmet Descriptions "For operations in hazard zones."
  4. ^ a b c Halo: Reach - Armory: Commando, Scout, and Security - CBRN/CNM Helmet Descriptions "For operations in hazard zones; command network module."
  5. ^ Halo: Reach - Armory: EOD Helmet model
  6. ^ Halo: Reach - Armory: HAZOP - CBRN/HUL Helmet Description "For operations in extremely hazardous environments; hardened uplink module."
  7. ^ Halo: Reach - Armory: Military Police - CBRN/HU/RS Helmet Description "For operations in hazard zones; hardened uplink/remote sensor package."
  8. ^ Halo: Reach - Armory: ODST - CBRN/HUL Helmet Description "For operations in hazard zones; hardened uplink module."
  9. ^ Halo: Reach - Armory: EOD UA/HUL - Helmet model
  10. ^ Halo Waypoint, Canon Fodder - Pen Umbra (Retrieved on Jun 19, 2021) [archive]