In this answer, I explain how there were two contractors that made the environmental control systems and their lithium hydroxide cartridges during the Apollo program. Garrett AiResearch made the ECS for the command module, with square cartridges. Hamilton Standard made the life support systems for the spacesuits -- and later the lunar module ECS -- with round cartridges.

How did the Shuttle's LiOH cartridges for the cabin and the EMUs compare in shape? Pictures would be helpful, as well as the identities of the contractors.


1 Answer 1


No, not at all.

The EMU Contaminant Control Cartridges (CCC) were rectangular.

enter image description here

Information on the CCC:

When ventilation gas returns from the HUT to the PLSS, it first passes through the CCC. As the ventilation gas flows through the cartridge to the fan, beds of chemicals remove CO 2 , odors, and contaminants, while filters remove particulates. Two versions of the CCC exist: a lithium hydroxide (LiOH) canister, and a Metal Oxide (Metox) canister. Both serve the same operational function; however, the LiOH canister is used for shuttle-based EVAs, and the Metox canister is used for ISS-based EVAs.

The cartridge is located in a compartment on the back of the PLSS under a TMG flap that unzips to provide access (Figure 3-17). It can be removed and replaced on orbit by a single IV crewmember without tools in less than 5 minutes. The canister can be replaced while a crewmember is in the suit, but the EMU must be in a pressurized environment. The CCC is changed out between successive EVAs.

The shuttle cabin cartridges were cylindrical.

enter image description here

Information on the cabin cartridges:

Odor and CO 2 are removed from the cabin air by the LiOH canisters. A flow orifice directs approximately 120 lb/hr of air through each of the two LiOH canisters (Figure 3-1). Activated charcoal in the canister controls odor; CO 2 is removed from the air when the CO 2 reacts with the LiOH to produce lithium carbonate. The LiOH canisters are changed out periodically during the mission on a predetermined schedule, generally one or two times per day based on the number of crewmembers. The LiOH canisters are located in the ECLSS bay and are accessible through the MD54G opening in the middeck floor (Figure 3-2). Up to 30 spare LiOH canisters are located in the ECLSS bay below Panel MD52M.

As far as contractors go, Hamilton Standard built the EMU PLSS. Rockwell was the orbiter contractor but Ham Standard also supplied a lot of the ECLSS components.


EMU Systems Workbook

Carbon Dioxide Removal - Thermodynamics

Environmental Control and Life Support System (ECLSS) Training Manual


EMU - Extravehicular Mobility Unit

EVA - Extravehicular Activity

HUT - Hard Upper Torso

IV - IntraVehicular

MD54G & MD52M - Shuttle middeck locations

PLSS - Portable Life Support System

TMG - Thermal / Micrometeorite Garment

  • 2
    $\begingroup$ (laugh) Doesn't surprise me that the shapes still differ, although the cabin/suit cartridge shapes are reverse of those from Apollo. $\endgroup$
    – DrSheldon
    Commented Apr 17, 2020 at 23:33

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