Presentation is loading. Please wait.

Presentation is loading. Please wait.

Space Environment Effects : Manned Volumes

Similar presentations


Presentation on theme: "Space Environment Effects : Manned Volumes"— Presentation transcript:

1 Space Environment Effects : Manned Volumes
Materials and Processes Division ESA/ESTEC/TOS-QM

2 Materials and Processes Division
Offgassing Materials and Processes Division ESA/ESTEC/TOS-QM

3 Materials and Processes Division
Offgassing test (1) ECSS-Q (former ESA PSS ) : The determination of offgassing products from materials and assembled articles to be used in a manned space vehicle crew compartment Purpose: Determine the identity and quantity of volatile offgassed products from materials and assembled articles. Material screening test Quantity of Carbon Monoxide [mg/g] Quantity of total organics (pentane equivalent) [mg/g] Identification of contaminants in excess of 10 mg/g of material General test for materials/assembled articles Identification and quantification of all contaminants present Use of T-values for acceptance Materials and Processes Division ESA/ESTEC/TOS-QM

4 Materials and Processes Division
Offgassing test (2) Acceptance Limits Screening test Carbon Monoxide : <25 mg/g material Total Organics : <100 mg/g material General test No definitive acceptability defined by this test. Data are evaluated by the Safety Office of the relevant project for assessment of toxic hazard due to volatile contamination evolved from the item under test for assessment of the impacts on the potential toxicity of the total quantity of offgassed products from all contaminant generating items for a given mission Materials and Processes Division ESA/ESTEC/TOS-QM

5 Materials and Processes Division
Offgassing test (3) Following primary acceptance criteria are relevant: The quantity of each individual offgassed product shall result in a predicted Spacecraft concentration below the SMAC value Toxic Hazard Index (T) shall not exceed 0.5. T is determined by calculating the ratio of the projected concentration of each offgassed product to its SMAC value and summing up these ratios for all offgassed products T = C1/SMAC C2/SMAC Cn/SMACn Materials and Processes Division ESA/ESTEC/TOS-QM

6 Offgassing test Procedure (1)
General test conditions Temperature 50 C Atmosphere : synthetic air or clean/dry air Pressure : 1 Atmosphere at 50 C Duration : 72 hrs Mass (material) 5g/liter test volume Sampling : +/- 250 ml gas on trap after max. 12 hrs recovery to reach RT; flow rate sampling is +/- 25 ml/min. Materials and Processes Division ESA/ESTEC/TOS-QM

7 Offgassing test Procedure (2)
Test chambers Different facilities are available e.g.: Heraeus ovens 128 and 718 liters Glass bottles 1, 2.5 and 5 liters Analyses: Screening: TO/CO GC with Methaniser and Flame Ionisation Detector General test Pre-concentrated sampling Desorption system : Model MW-1A from Rektorik (CH) GC with DB5MS from JW column (60m, diam 0.25mm, film 0.25 mm) Mass spectrometer model Profile from Kratos (UK) Materials and Processes Division ESA/ESTEC/TOS-QM

8 Offgassing test Procedure (3)
Screening test Materials and Processes Division ESA/ESTEC/TOS-QM

9 Offgassing test Procedure (4)
Materials and Processes Division ESA/ESTEC/TOS-QM

10 Materials and Processes Division
Odour Test NASA-STD-6001 (former NHB C) Purpose Determine if the odour is objectionable or revolting Odour of a material or assembled article is objectionable or revolting if an average of 2.5 or higher on an odour characteristic scale is obtained (0:undetectable, 1:Barely detectable, 2: Easely detectable, 3: objectionable,4: revolting). Sample preparation is the same as for Offgassing test Test panel shall consist of 5 qualified persons Materials and Processes Division ESA/ESTEC/TOS-QM

11 Materials and Processes Division
Flammability Materials and Processes Division ESA/ESTEC/TOS-QM

12 Flammability configuration assessment (1)
Identify flammable materials used, their amounts, thickness, exposed surface, exposure environment Identify propagation paths for exposed materials (including housing) If configuration is container, evaluate its capability to contain an internal fire If unacceptable configuration through the configuration assessment, there are two options: Use fire break concepts to reduce flammability hazard by isolating the flammable materials Conduct a test to show acceptability of configuration Materials and Processes Division ESA/ESTEC/TOS-QM

13 Flammability configuration assessment (2)
Materials and Processes Division ESA/ESTEC/TOS-QM

14 How to reduce flammability hazards
Limitation of flammable materials by replacement with a non flammable one Restriction of propagation paths through Covering of flammable materials with a non flammable one Separation of flammable materials (avoid propagation) Materials and Processes Division ESA/ESTEC/TOS-QM

15 Upwards Propagation Test (1)
ECSS-Q (Former ESA PSS ) : Flammability testing for the screening of space materials Purpose : Determine if a material, when exposed to a standard ignition source, will self-extinguish and not transfer burning debris, which can ignite adjacent materials Test criteria : Self extinguishing within 15 cm No transfer of burning debris Burn Propagation time Sample dimensions : 300 x 64 mm, worst case thickness Test atmosphere : depends on application (24% O2 or more…) Materials and Processes Division ESA/ESTEC/TOS-QM

16 Upwards Propagation Test (2)
Materials and Processes Division ESA/ESTEC/TOS-QM

17 Upwards Propagation Test (3)
Materials and Processes Division ESA/ESTEC/TOS-QM

18 Upwards Propagation Test (4)
Materials and Processes Division ESA/ESTEC/TOS-QM

19 Wire Flammability test (1)
ECSS-Q (Former ESA PSS ) : Flammability testing for the screening of space materials Purpose : Determine if a wire insulation system, when exposed to an external ignition source, will self-extinguish and not transfer burning debris, which can ignite adjacent materials Acceptance criteria Prior to flame application, while heating wire to maximal operation T, no spontaneous combustion, splitting insulation nor baring conductor During ignition and combustion no flaming droplets/particles After burner is extinguished, cease flaming within 10 s and within a total burn length of 150 mm Sample dimensions : 5 x 1m Test atmosphere : depend on application (20% O2 or more…) Materials and Processes Division ESA/ESTEC/TOS-QM

20 Wire Flammability test (2)
Materials and Processes Division ESA/ESTEC/TOS-QM

21 Wire Flammability test (3)
Materials and Processes Division ESA/ESTEC/TOS-QM


Download ppt "Space Environment Effects : Manned Volumes"

Similar presentations


Ads by Google