GB/T 47448-2026Environmental control requirements for spacecraft assembly, integration and test (English PDF)

6.1 Temperature

6.1.1 Temperature Requirements The temperature requirements are as follows:

a) The operating temperature of the spacecraft's AIT (Autonomous Intervention) system should be 20°C±5°C. Any other special requirements shall be implemented in accordance with relevant regulations.

b) When transporting spacecraft outside the factory, temperature-controlled packaging containers should be used, and the temperature inside the packaging containers should preferably be controlled at 5°C. 35°C, or follow the specific design documents, and real-time monitoring is recommended.

6.1.2 Temperature control requirements Temperature control requirements are as follows:

a) Equipment that is significantly affected by ambient temperature should not be used in the AIT process; if it is used, temperature control measures should be implemented for the equipment.

b) When excessively high local ambient temperatures during spacecraft testing affect its instruments and equipment, cooling measures should be taken, such as using non-thermal methods. Pollution-reducing methods such as air cooling;

c) Temperature control measures should be implemented and monitoring and alarm functions should be activated for temperature-sensitive spacecraft components or parts;

d) For temperature changes caused by operations in confined spaces (such as manned reentry capsules), ventilation or heat dissipation control measures should be implemented;

e) Environmental control capabilities should meet the heat dissipation requirements of specific tests, such as spacecraft system-level thermal tests.

6.2 Humidity

6.2.1 Humidity Requirements Humidity requirements are as follows:

a) The relative humidity of the spacecraft's AIT working environment should be 30%~60%. For other special requirements, the relevant documents shall apply.

b) The relative humidity inside the packaging container should not exceed 60%, or as specified in the design documents.

6.2.2 Humidity Control Requirements Humidity control requirements are as follows:

a) The AIT process should not have a significant impact on ambient humidity (e.g., spraying is not permitted during floor cleaning, and humidification should not be carried out). (To address the impact on spacecraft)

b) For humidity-sensitive spacecraft components or parts (such as solar panel propulsion mechanisms), local dehumidification devices should be used to control humidity;

c) For humidity-sensitive operations, such as soldering electronic components, dehumidification or humidification devices should be used to control the local humidity environment;

d) The humidity inside the packaging container should be controlled by means of air conditioning, desiccant, and nitrogen gas to ensure the safety of the spacecraft surface. It will not condense.

6.3 Cleanliness and Contamination

6.3.1 Cleanliness Requirements The cleanliness level of the AIT working environment of the spacecraft should be ISO Class

8.Other special requirements shall be implemented in accordance with the relevant documents.

6.3.2 Cleanroom Control Requirements The cleanroom control requirements are as follows:

a) Cleaning of the cleanroom shall be carried out in accordance with section

4.6 and Appendix F of GB/T 25915.5-2010;

b) A positive pressure difference should be maintained between the cleanroom and the outside environment; the pressure difference between cleanrooms (areas) of different grades should not be less than

5 Pa. The pressure difference between the clean area and the non-clean area should not be less than

5 Pa, and the pressure difference between the clean area and the outside should not be less than

c) Activities that generate pollutants, such as machining, should not be carried out in clean areas (rooms). If machining is absolutely necessary under special circumstances, [further procedures should be followed]. Take safe and effective control measures to remove excess material;

d) For cleanrooms with microbial control requirements, in addition to routine cleaning as described in a), sterilization should also be performed.

6.3.3 Requirements for personnel pollution control The requirements for personnel-related pollution control are as follows:

a) Cleanroom garment contamination control shall be carried out in accordance with section

4.2 and Appendix B of GB/T 25915.5-2010;

b) Contamination control for personnel entering the clean area shall be carried out in accordance with section

6.4 Vibration and Noise

6.4.1 Vibration and Noise Requirements The vibration and noise requirements are as follows:

a) The background noise level in general AIT work areas should not exceed 70 dBA. Personnel in control rooms and other similar areas need to concentrate or communicate effectively. The background noise level in such locations should not exceed 60 dBA.

b) The steady-state noise sound pressure level of short-term noise generated by special tests (such as vibration tests, noise tests, etc.) should not exceed 85 dBA.

c) Weak signal testing (such as micro-vibration, noise assessment inside manned spacecraft, etc.), the background noise signal-to-noise ratio should be higher than 10dB. Calculate according to formula (1).

6.4.2 Vibration and Noise Control Requirements Vibration and noise control requirements are as follows:

a) For work items sensitive to vibration and noise (such as micro-vibration testing, precision testing, quality characteristic testing, etc.), a comprehensive evaluation of vibration and noise should be conducted. The impact of noise;

b) When ground equipment generates significant vibration as a vibration source, appropriate measures should be taken, such as selecting low-vibration equipment and using vibration-damping materials. The assessment methods for vibration and its impact on structures shall be carried out in accordance with GB/T 14124;

c) For equipment exceeding noise standards, necessary measures should be taken, such as optimizing equipment space layout, constructing enclosures, installing silencers, and using shielding (soundproof barriers). Measures to effectively prevent the spread of noise shall be implemented in accordance with GB/T 17249.2.

d) High-noise environments generated by special tests (such as noise tests, vibration tests, etc.) should be monitored and evaluated regularly;

e) In workplaces with high vibration or noise levels, it is advisable to take protective measures such as wearing earmuffs or earplugs;

f) Micro-vibration tests should take measures to reduce ambient background noise (e.g., conduct tests at night to reduce the impact of traffic on the test environment). (Impact, shutting down the air conditioning system, using vibration isolation devices, controlling personnel movement, reducing noise, etc.)

g) Strong noise sources in AIT working areas, such as reverberation chambers, should be subject to targeted noise reduction designs (e.g., sound insulation and airtightness of reverberation chamber doors, sound attenuation). (e.g., sound insulation design of roads)

h) Strong vibration sources in the AIT working area, such as vibration tables, should be subject to targeted vibration isolation design. After vibration isolation, the vibration environment indicators should not exceed [the specified limits]. 0.05g;

i) Equipment such as those used for thermal testing that are equipped with high-pressure exhaust pipes should be equipped with appropriate noise reduction measures.

6.5 Electrostatic Protection

6.5.1 Electrostatic Discharge Protection Requirements Before spacecraft AIT (Automatic Interchange), the electrostatic discharge (ESD) sensitivity of spacecraft components should be identified. For ESD sensitivity indicators... For products that meet the standard of not less than 100V for the Human Body Model (HBM) and not less than.200V for the Charged Device Model (CDM), the electrostatic discharge (ESD) protection requirements shall be as follows: The provisions of Chapter 5 of GB/T 32304-2015 and GB/T 41673-2022 shall apply; otherwise, stricter control measures shall be taken.

6.5.2 Static Electricity Control Requirements

6.5.2.1 Requirements for the Configuration of Anti-static Work Areas The requirements for configuring an anti-static work area are as follows:

a) The AIT (Autonomous Interchange) work area on spacecraft should be identified, divided, and marked according to the electrostatic protection requirements of aerospace products;

b) The EPA shall configure the necessary electrostatic discharge protection equipment, facilities and devices in accordance with the requirements specified in

5.3.7.6 of GB/T 32304-2015. Materials, etc.;

c) All facilities, equipment, antistatic materials, clothing, supplies, tools, and packaging related to electrostatic protection requirements shall be calibrated and certified as qualified. It has been put into use.

6.5.2.2 Requirements for personnel electrostatic protection control The requirements for personnel electrostatic discharge protection and control are as follows:

a) Personnel should wear anti-static clothing and pass a body resistance tester before entering the EPA;

b) When handling ESDS electronic products, operators should connect to the grounding system via a wrist strap system and a floor-to-shoe strap system;

c) When operators are working at an anti-static workbench or fixed workstation, they should wear an anti-static wrist strap connected to the grounding system. For the ground system, the system resistance should meet the requirement of 1×10^6Omega~3.5×10^7Omega;

d) When moving around or wearing wrist straps is inconvenient, antistatic shoes, antistatic shoe covers, or heel straps should be worn, and the floor-shoe harness system should be used. Grounding is required, and the system resistance should be between 1×10^5Omega and 1×10^9Omega. The human body voltage should be less than 100V.

6.5.2.4 Spacecraft Electrostatic Control Requirements The electrostatic control requirements for spacecraft are as follows:

a) Electrical connector interfaces on spacecraft should be protected with isolation measures (such as anti-static protective covers);

b) ESDS products should be transported using equipment or packaging with anti-static properties;

c) Electrostatic protection of spacecraft during AIT process shall comply with the provisions of Chapter 6 of GB/T 41673-2022.

6.6 Electromagnetic Environment

6.6.1 Electromagnetic Environment Requirements The electromagnetic environment requirements are as follows:

a) The maximum electromagnetic radiation exposure limits for personnel in the AIT area should meet the requirements of Tables 2 to 5 to avoid electromagnetic radiation harming the human body. It has a harmful effect;

6.6.2 Electromagnetic Environment Control Requirements The electromagnetic environment control requirements are as follows:

a) Warning signs must be posted in work areas where electromagnetic radiation levels exceed specified limits (e.g., high-power radio testing areas). Electromagnetic environment monitoring is necessary.

b) During system-level EMC testing or antenna performance testing (near field, far field, compact field), the area outside the anechoic chamber or subject to external interference should not be exposed. To avoid interference and potential injury or impact on test results;

c) The EMC test site should have an independent grounding lead, the grounding resistance should be less than 1Omega, and the grounding terminals should be centrally located at the power supply and... Near the signal filter;

d) The background magnetic field environment should meet the requirements of the magnetic test, and real-time monitoring of magnetic field fluctuations should be carried out during the magnetic test;

e) In the process of measuring weak signals (such as micro-vibration measurement, thermocouple measurement, mass measurement, electrical measurement, etc.), filtering, shielding, grounding, etc. should be used. Isolation and other measures are implemented to avoid electromagnetic interference caused by power supply quality issues, ground wire crosstalk, etc.

f) During the AIT process of a spacecraft, shielding, isolation and other protective measures should be taken for electromagnetically sensitive devices or parts (such as receivers).

6.7 Radiation

6.7.1 Radiation Requirements During AIT operations involving radioactive sources or radiation devices, radiation monitoring should be conducted and protective measures should be taken.

6.7.2 Radiation Control Requirements Radiation control requirements are as follows:

a) Operations involving devices carrying radioactive sources should be conducted by qualified personnel, and personal dose monitoring should be performed on the operator. For archiving, the average dose over five consecutive years should not exceed 20 mSv, and the dose in any single year should not exceed 50 mSv;

b) Workers should wear personal radiation dose monitors and personal protective equipment (such as lead vests and lead glasses);

c) An isolation zone should be established within the radiation work area, and clearly visible radiation warning signs and monitoring alarm devices should be installed in appropriate locations. [Further details about radiation work are not provided.] Unauthorized personnel are prohibited from entering to prevent accidental exposure.

d) Work related to the radiation source should be carried out in the final stage of the spacecraft's AIT activities, minimizing the time spent on such work and keeping it as close as possible to the radiation source. The furthest and involving the fewest people;

e) Radiation leaks that may occur from nuclear-powered spacecraft should not affect the spacecraft itself or other spacecraft systems.

6.8 Lighting

6.8.1 Illuminance Requirements Unless otherwise specified, the illuminance requirements are as follows:

a) The illuminance in the spacecraft AIT working environment and the pipeline welding area should not be less than 300 lx;

b) The illuminance uniformity within the clean area should be no less than 0.7, and the illuminance uniformity of adjacent areas should be no less than 0.5.

6.9 Gas Supply

6.9.1 Gas Supply Requirements The gas supply requirements are as follows:

a) The gases used in the AIT (Autopilot Intake) process of spacecraft should meet the requirements for purity, cleanliness, dew point, etc., such as the helium used for leak rate testing. The purity is not less than 99.99%, and the purity of nitrogen is not less than 99.99%.

b) The compressed air used within the plant area shall meet the requirements of GB/T 13277.1-2023 regarding compressed air pressure, cleanliness, oil contamination, and dew point. Requirements such as. the quality of hot vacuum compressed air must meet the Level 3 requirement in GB/T 13277.1-2023.

6.10 Power Supply and Distribution

6.10.1 Power Supply and Distribution Regulations The power supply and distribution regulations within the factory building are as follows:

a) Low-voltage distribution boxes (cabinets, panels), power grid grounding systems, etc., configured in the spacecraft AIT work area workshop shall comply with GB 50052- 2009 regulations and the load requirements of the work area factory buildings;

b) The power quality of the spacecraft AIT process shall comply with the provisions of GB/T 12325-2008.

6.10.2 Power Supply and Distribution Control Requirements The power supply and distribution control requirements are as follows:

a) The power distribution system within the spacecraft's AIT (Air-Independent Testing) work area should be matched to the load and should not exceed the rated power; 220V or 380V single... When electrical equipment is connected to a 220V/380V three-phase system, the three phases should be balanced and the leakage protection should meet the requirements.

b) Low-voltage distribution boxes (cabinets, panels), fixed power sockets, and grounding terminals in the spacecraft AIT working area should be fixed in place and securely installed; The bottom of indoor floor-mounted distribution boxes (cabinets, panels) should be at least 50mm above the ground, and the center point of fixed distribution boxes should be perpendicular to the ground. The distance should be 1.4m to 1.6m; there should be no obstructions within 1.2m in front of or below the distribution box (cabinet, panel).

c) The voltage deviation of the three-phase power supply at 20kV and below in the spacecraft AIT operating area is ±7% of the nominal voltage, within the same power supply and distribution environment. The power supply phase sequence should be clockwise; the voltage deviation of a 220V single-phase power supply should be 7%-10% of the nominal voltage, and the neutral-to-ground voltage should be greater than [value missing]. 0V less than or equal to 5V; suitable for applications with small short-circuit capacity at the power supply point, long power supply distance, and special requirements for power supply voltage deviation. The users are determined by both the power supplier and the power consumer.

d) The power distribution system within the spacecraft AIT working area should preferably be equipped with a backup power supply or uninterruptible power supply (UPS) system, and should be installed in a clean, shaded area. Store in a cool, dry environment, away from direct sunlight and other heat sources; high-power UPS (10kVA and above) should not be stored there. Inside the AIT lobby, the ambient temperature at the storage site is generally between 20°C and 28°C, and the relative humidity is between 20% and 90%. Disinfection of the storage site is also required. Fire prevention facilities and equipment should be intact and complete, free of open flames and flammable materials, and have measures to prevent small animals from entering; based on backup power supply or The UPS user manual specifies regular maintenance and upkeep.

e) Low-voltage distribution boxes (cabinets, panels), fixed power sockets, grounding terminals, and mobile power converters in the spacecraft AIT work area should be regularly... Verification is required, and the product must be used within the verification validity period.

f) For equipment with special power requirements, the leakage current protection of the distribution cabinet (cabinet, panel) should be increased while ensuring power safety. He should not use electrical equipment.

g) A dedicated charging area should be set up in the spacecraft AIT hall, with proper area isolation and remote monitoring facilities.

6.10.3 Power supply and distribution grounding requirements The grounding requirements within the spacecraft AIT work area are as follows:

a) The grounding system of the spacecraft's AIT working area should preferably adopt a common grounding system, and each type of grounding should be reliably connected to the common grounding device. Furthermore, it should meet the requirements of GB 14050-2008.

b) The grounding system for the spacecraft's AIT working area should preferably be a TN-S system. If this is not possible, a TN-CS system may be used, with the same power supply. Low-voltage electrical systems should not simultaneously employ TN, TT, or IT systems. The grounding methods of different low-voltage systems should comply with the appendix. The rules for recording C.