USSRC Proprietary 2012 art credit: NASA ISS image:

ECLSS PANELS Orbiter ML31C Middeck Left L1 & L2 MEDS – Multi-function electronic Display System retrofitted to Atlantis 1999 Photo Credit NASA USSRC Proprietary 2012

Graphic: USSRC Proprietary 2012

ECLSS: AirEarth 1. ~79% Nitrogen 2. ~21% Oxygen 3. < 1% Trace Elements 14.7 psi Earth’s Atmosphere USSRC Proprietary 2012

Pressurization System: Orbiter Components 1.80% Nitrogen (11.2 psi*) 2.20% Oxygen (3.5 psi*) 3. Pressure varies: a.14.7 nominal b.16.7 cabin leak check c.10.2 before EVA *Partial pressures do not correspond to percentages. N 2 & O 2 stored mid-fuselage USSRC Proprietary 2012 ECLSS: AirOrbiter

Pressurization System Station Components 1.80% N % O 2 3.Pressure 14.7 psi Station Supply  N 2 & O 2 tanks: Progress resupply vehicles  O 2 source: electrolysis  Backup O 2 : solid cartridges (exothermic) Oxygen Hydrogen Electrolysis Graphic: USSRC Proprietary 2012 ECLSS: AirStation

USSRC Proprietary 2012 Air Revitalization System (ARS): —cleans used air A. Microfilters: trap dust, crumbs, hair, skin cells, etc. B. LiOH canisters: remove CO 2 (carbon dioxide) C. ATCO: turns CO into CO 2 (Ambient Temperature Catalytic Oxidizer) LiOHCanisters ECLSS: AirOrbiter

Air Revitalization System (ARS): cleans used air A.Gas Analyzers: check levels of O 2, toxic gases; O 2 added automatically as needed (Metox canisters) B.(CDRA) Carbon Dioxide Removal Assembly: rechargeable CO 2 removers (Metox canisters) C.(TCCS) Trace Contaminant Control Subassembly: filters gas contaminants with charcoal D.Harmful Impurities Filter – backs up TCCS USSRC Proprietary 2012 ECLSS: AirStation

Air Revitalization System (ARS): Heat Exchanger Nominal temperature: 65-80°F (18-27°C) Nominal humidity: 35-60% Cabin air passes or bypasses heat exchanger Station temperature & humidity more consistent & homogeneous than that of the orbiter USSRC Proprietary 2012 ECLSS: Air Orbiter & Station

Supply and Waste Water – Panel ML31C A.Fuel Cells produce water as a by-product of electricity must be periodically purged to provide peak performance B.5 tanks: 75 gallons total A – drinking water B,C,D – cooling system E – waste water USSRC Proprietary 2012 ECLSS: WaterOrbiter

Supply and Waste Water Finite supply brought via unmanned resupply vehicles: Progress (Russia), ATV (ESA), HTV “Kounotori” (JAXA) May 2009: Expedition 19—total recycling via Boeing’s Water Recovery and Management Subsystem USSRC Proprietary 2012 ECLSS: WaterStation

Active Thermal Control System (ATCS) a)Water Coolant Loops b)Water-Freon Exchanger c)Freon Coolant Loops d)Radiator Panels (PB doors) e)Flash Evaporators topping evaporators high load evaporators ammonia evaporators USSRC Proprietary 2012 ECLSS: T emperature Orbiter

Common Cabin Air Assembly A.Similar to coolant loops & ATCS on orbiter B.Water coolant in racks, ammonia to radiators C.Ventilator locations: 1.Individual racks 2.Within modules 3. Between modules ECLSS : Temp—Station Only USSRC Proprietary 2012

Reading your checklists!!! T- 04:30 APU PRE-START RECEIVE GO FOR APU PRE START P R2 BOILER N2 SUPPLY (3) - ON BOILER CNTLR (3) – ON BOILER CNTLR PWR/HTR (3) - A APU FUEL TK VLV (3) - CLOSE APU FUEL PUMP/VLV COOL (2) - OFF HYD CIRC PUMP (3) - ON APU CNTLR PWR (3) - ON HYD MAIN PUMP PRESS (3) - LOW APU AUTO SHUT DOWN - ENABLE APU SPEED SELECT (3) - NORM APU CONTROL (3) - OFF C2 KEYPAD GPC/CRT 6 EXC [ADVISE OTC APU'S READY FOR START]

USSRC Proprietary 2012 ECLSS regulates 3 things: Air - pressure & revitalization Temperature Water – supply & waste Nominal air components: N2 – 80% (11.2 psi) O2 – 20 % (3.5 psi) Nominal Temp & Humidity: F, 35-60% ECLSS Review

USSRC Proprietary 2012 Nominal Pressures: 14.7 psi, on orbit (orbiter & ISS) 16.7 psi (orbiter) cabin leak check 10.2 psi (orbiter) pre-EVA Air cleaning methods (orbiter) ARS microfilters LiOH canisters ECLSS Review

USSRC Proprietary 2012 What process cleans fuel cells? Purge 2 orbiter coolants: water and freon 2 Station coolants: water and ammonia ECLSS Review

USSRC Proprietary 2012 ECLSS Review Use flash evaporators when: PBD closed Which evaporators will move you? High load Use ammonia flash evaps when: Below 100,000 feet Good Luck on your EDM!