Safety TIM September 23 rd , 2004

1. Safety TIM September 23rd, 2004 Safety TIM

2. Experiment development Team : • Principal Investigator: Mr R. Battiston (Perugia) • Magnetometer:Mr V. Sgrigna (Roma III) • Alteino experiments :Mr P. Picozza (Roma II) • System engineer (Mech):Mr S. Rossi (SERMS Terni) • System engineer (Electr) :Mr A. Papi (INFN Perugia) • Verification and testing :Mr S. Ascani (SERMS Terni) • Trigger :Mr M. Casolino (Roma II) , Mr. A. Popov (MEPHI) • Ladders :Mr M. Ionica (INFN Perugia) • Integration :Mr L. Valentini (Ferrari) • PC architectural:Mr L. Conti (Roma III) • Software development :Nergal srl (Roma) • Product assurance :Kayser Italia srl (Viareggio) • Safety :Kayser Italia srl (Viareggio) Safety TIM

3. Main Scientific Objectives • LAZIO/SIRAD experiment aims: • To perform a number of measurements of cosmic ray in space, • To understand their relation to anomalous phosphene (Light Flash) perception by astronauts, • To study the effect of different shielding materials to reducing the radiation environment. For this purpose the Alteino equipment already on orbit will be used • Characterize the magnetic environment inside the ISS. • To perform a first test in space of a sensor capable of monitoring with high accuracy the short time stability of the Vabn Allen belts, to study the possibility of precursor earthquake related phenomena. Safety TIM

4. Experiment description • To meet these goals we plan to realize a high performance cosmic ray detector, LAZIO/SIRAD, to measure and identify all particles traversing the detector separating nuclei from electrons/positrons, in the energy range ~10 to ~100 MeV. It will record their time of arrival, their line of arrival (pitch angle), their direction of arrival. A very important feature of LAZIO/SIRAD equipment is its very large aperture (~60 cm2 sr ) which will allow to perform accurate, real time measurements of the pitch angle distribution within short time intervals (from few seconds to few minutes depending on the position on the orbit). • LAZIO is equipped with a high precision low frequency magnetometer, which will be used to measure the intensity and the variations of the magnetic field within the ISS, in correlating these measures with the measurements of the particle fluxes. Safety TIM

5. State of the Art • Electronics boards exists for Silicon and Trigger readout and power, to be refurbished. • Silicon detectors are being refurbished. • Trigger hardware is being built by the Russian partners. • Magnetometer boards are being developed (if late, they will not be installed). • Mechanics being designed and qualified. • PC based on PC104plus commercial series. Safety TIM

6. Experiment hardware: Safety TIM

7. LAZIO Main Electronic Box Safety TIM

8. MEB hardware: • The MEB contains: • the ionizing radiation detectors: • silicon detectors • plastic scintillators • the experiment electronics: • data acquisition • power supply • on board computer (PC 104 architecture) • On board software • The MEB acquires and store data on internal PCMCIA high density cards. Safety TIM

9. Main Electronic Box hardware • The E-box consist of a bottom part and of a cover made of aluminium alloy (AL7075) with Alodined 1200 bolted together by means of ???? screws. • The PCB’s are mounted on top of each others by means of bolts and spacers between the pcb’s. • The E-box housing is a vented container. Indicate how many vented holes • A power cable connect the electronic box to ISS – (28 +/- 0.5 V – 1.5 A in nominal conditions) Safety TIM

10. Safety TIM

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13. Magnetometer box Safety TIM

14. Voice recorder and its batteries Safety TIM

15. Simplified Flight operations • Extract the LAZ hardware from the Progress (30 min); • install/connect the MEB, MB and MH. Connect the power cord to the ISS bus and the ground cord to the ISS chassis (60 min); • Switch on the LAZ MEB and put on EVENT MODE; • The PCMCIA need to be replaced when they are full of data. A blinking light will inform the astronaut that this operation is required (5 min); • The magnetometer requires to be mounted in different directions every TBD days • Once the mission is completed, the LAZ experiment will be switched from EVENT to INTEGRAL mode for additional data taking during the increment 11 (5 min). • During incremente 11, every few weeks, the PCMCIA board should be replaced when filled (flashing light), and stored (10 minutes); • When the Increment 11 is completed, less than 10 PCMCIA boards will be downloaded from ISS using the Soyuz. Safety TIM

16. MEB Structural Safety and Verification • An hard mounting is foreseen during upload of MEB. All the rest of the items will be launched in a soft stowed pouch. • Designed to survive depressurization and repressurisation at a rate of 100mm Hg/s. Indicate for how many times? Do you foresee to produce a fatigue analysis? • Verification • Structural Verification Plan • Structural analysis • Fracture control plan • Fracture control report • Fastners integrity plan • Vibration tests Safety TIM

17. MEB fusing, grounding, bonding & inhibits • Electrical shock • Describe grounding philosophy – redundant grounding with Pin and grounding strap? • High DC voltage: Secondary voltage greater than 32 V Indicate all the voltage levels you have. • Hazard controlled by galvanic insulation and DC/DC converter which is fully enclosed in the electronic box. Crew access is not possible. Is this correct? • Mating/demating: Indicate how many connectors to mate and demate you have. In case the fuse blowing current is above 3 A you need an upstream inhibit: Mechanical switch at 28 V inlet Indicate also that the wire sizes will according to interpretation letter TA-92-038 Safety TIM

18. MEB electrical ISS interfaces Safety TIM

19. MEB Grounding/Bonding diagram Safety TIM

20. MEB Electrical circuit diagram Safety TIM

21. MEB Human factors – touch temperature • Nominal consumption power: 42 W • Thermal design: Passive or active describe little bit the thermal design • The touch temperature of the MEB surface is < 49°C under the worst case conditions (specify worst case conditions – how many failures?) see thermal analysis ref number • Any protection circuit? Thermal sensors? • Verification • Thermal analysis Safety TIM

22. MEB Electromagnetic and other radiations • EMC tests will be performed in flight configuration in accordance with SSP 30238 and IFOC annex 1 MEB Sharp edges, corners and protusions • Designed and inspected for compliance with NASA-STD-3000 / SSP 505005 Safety TIM

23. Lithium battery for PC 104 (safety aspects and qualification) • Make a description: which type of lithium batteries button cell? They are not in the PCB • Qualification (It is valid in case C< 300mAh otherwise a unique hazard will be generated): • Open voltage test • Loaded measurement before and after leak test Safety TIM

24. Alkaline batteries for voice recorder(safety aspects and qualification) No particular problems if they are pure alkaline, they are less than 6, they are Dsize or smaller, they are in serires configuration or in parallel configuration. No series/parallel Safety TIM

25. Limited Life Items • Indicate the list if already known Safety TIM

26. Flammability • MAPTIS related materials will be selected where possible. DML will be submitted to ESA for approval Safety TIM

27. Maintainability • Maintainability is not foreseen on orbit Safety TIM

28. Alteino equipment to be used in this experiment • The warranty period of Alteino needs to be checked Did you check, Can we give a final answer to the safety panel? • The Shielding tiles will be fixed (in which way?) to Alteino detector • Flammability potential hazard Safety TIM

29. Flammability assesment for shielding tiles • Any idea how to control this hazard. No possibility to put some kind of not flammable coating? Safety TIM

30. Hazard reports • STD HAZARD Report N° : STD-LAZ • UNIQUE HAZARD Report N°: • LAZ-01 : Structural failure • LAZ-02 : high DC voltage • LAZ-03: Batteries in case you are out of the requirement mentioned previously Safety TIM