ISO 15388:2022 宇宙システム — 汚染および清浄度管理 | ページ 6

3.1.1

bakeout

activity of increasing the temperature of hardware to accelerate its outgassing (3.1.28) rates with the intent of reducing the content of molecular contaminants (3.1.11) within the hardware

Note 1 to entry: Bakeout is usually performed in a vacuum environment but may be done in a controlled atmosphere.

3.1.2

bioaerosol

dispersed biological agents [e.g. viable particles (3.1.29) , allergens, toxins or biologically active compounds of microbial origin] in a gaseous environment

3.1.3

biocontamination

contamination of materials, devices, individuals, surfaces, liquids, gases or air with viable particles (3.1.29)

3.1.4

clean bench

table or bench-top working surface where a filtered airflow is concentrated across the bench top

Note 1 to entry: These bench tops have an established classification of maximum allowable airborne contaminants (3.1.11) .

3.1.5

cleanliness level

established maximum allowable amount of contamination in a given area or volume, or on a component

Note 1 to entry: The term may also apply to the predicted or measured extent of contamination.

3.1.6

cleanliness requirement specification

CRS

document that defines and identifies the spacecraft items and the environmental areas which are sensitive to contamination, the acceptable contamination levels at beginning and end of life and the applicable contamination environment

3.1.7

cleanroom

room within which the number concentration of airborne particles (3.1.29) is controlled and classified, and which is designed, constructed and operated in a manner to control the introduction, generation and retention of particles inside the room

Note 1 to entry: The class of airborne particle concentration (3.1.30 and 3.1.31) is specified.

Note 2 to entry: Levels of other cleanliness attributes such as chemical, viable or nanoscale concentrations in the air, and also surface cleanliness (3.1.39) in terms of particle, nanoscale, chemical and viable concentrations might also be specified and controlled.

Note 3 to entry: Other relevant physical parameters might also be controlled as required, e.g. temperature, humidity, pressure, vibration and electrostatic.

[SOURCE:ISO 14644-1:2015, 3.1.1]

3.1.8

cleanroom garment

clothing designed, manufactured and worn specifically to prevent contamination of hardware by personnel working in the cleanroom (3.1.7)

Note 1 to entry: Cleanroom garments include all items worn by personnel, such as coveralls, frocks, gloves, boots, finger cots and beard covers.

3.1.9

clean zone

defined space within which the number concentration of airborne particles (3.1.29) is controlled and classified, and which is constructed and operated in a manner to control the introduction, generation and retention of contaminants (3.1.11) inside the space

Note 1 to entry: The class of airborne particle concentration (3.1.30 and 3.1.31) is specified.

Note 2 to entry: Levels of other cleanliness attributes such as chemical, viable or nanoscale concentrations in the air, and also surface cleanliness (3.1.39) in terms of particle, nanoscale, chemical and viable concentrations might also be specified and controlled.

Note 3 to entry: A clean zone(s) can be a defined space within a cleanroom (3.1.7) or might be achieved by a separative device. Such a device can be located inside or outside a cleanroom.

Note 4 to entry: Other relevant physical parameters might also be controlled as required, e.g. temperature, humidity, pressure, vibration and electrostatic.

[SOURCE:ISO 14644-1:2015, 3.1.2]

3.1.10

collected volatile condensable material

CVCM

mass that outgasses from a material and subsequently condenses on a collector, expressed as a percentage of the initial specimen mass

3.1.11

contaminant

unwanted molecular or particulate matter that can affect or degrade the relevant performance or lifetime of the hardware to which it is attached

3.1.12

contamination

introduction of any undesirable molecular or particulate matter (including microbiological matter) into an item or into the environment of interest

[SOURCE:ISO 10795:2019, 3.62]

3.1.13

contamination and cleanliness control programme

organized effort to establish and achieve acceptable cleanliness and contamination levels during all phases of the space system project

3.1.14

contamination and cleanliness control plan

CCCP

document that describes how to implement a contamination and cleanliness control programme (3.1.13) , as either an independent document or a part of the consolidated project plan

3.1.15

contamination budget

allowable levels of contamination of hardware at each phase of ground and flight operations

3.1.16

contamination profile

contamination-related conditions in each phase of ground and flight operations

Note 1 to entry: Conditions include airborne particulate cleanliness classes, pressure, humidity, temperature, number of personnel engaged in operations, cleaning activities, outlines of facilities and so on.

Note 2 to entry: The contamination profile is part of the contamination and cleanliness control plan (CCCP) (3.1.14) .

3.1.17

cross-contamination

transfer of contaminants (3.1.11) from one surface or component to another

Note 1 to entry: Transfer can occur by migration along a surface, by physical contact, airborne as an aerosol, or as a gas or molecular matter.

3.1.18

debris

solid objects with their largest dimension greater than approximately 1 mm (1 000 μm) in size

3.1.19

electrostatic discharge

ESD

electrical breakdown of dielectric or gas or vacuum gaps, and also of surface interface of dissimilar materials, caused by differential charging of parts of dielectric materials and their interfaces

[SOURCE:ISO 11221:2011, 2.10, modified — The abbreviated term"ESD" has been added.]

3.1.20

generally clean

free from manufacturing residue, dirt, oil, grease, processing debris (3.1.18) , or other extraneous contamination based on visual examination

Note 1 to entry: This level does not apply to hardware that is sensitive to contamination.

[SOURCE:ISO 14952-1:2003, 2.12, modified — The abbreviated term"GC" has been removed.]

3.1.21

ground support equipment

GSE

non-flight systems, equipment or devices necessary to support the operations of transporting, receiving, handling, assembly, inspection, test, checkout, servicing, launch and recovery of a space system at launch, landing or retrieval sites

[SOURCE:ISO 14625:2007, 3.1.5]

3.1.22

interface control document

ICD

specification that describes the characteristics that must be controlled at the boundaries between systems, subsystems and other elements

3.1.23

microorganism

microscopical individual constituted to carry out life functions

Note 1 to entry: Microorganisms include organisms such as bacteria, protozoa, yeasts, moulds, fungi, algae and organisms that depend upon other life forms for reproduction such as viruses and parasites.

Note 2 to entry: Multicellular organisms and agglomerations of microorganisms may be visible to the unaided eye.

3.1.24

molecular contamination

contamination due to deposition of molecules on surfaces or their presence in gases or liquids

3.1.25

at-rest

condition where the cleanroom (3.1.7) or clean zone (3.1.9) is complete with equipment installed and operating in a manner agreed upon, but with no personnel present

[SOURCE:ISO 14644-1:2015, 3.3.2]

3.1.26

operational

agreed condition where the cleanroom (3.1.7) or clean zone (3.1.9) is functioning in the specified manner, with equipment operating and with the specified number of personnel present

[SOURCE:ISO 14644-1:2015, 3.3.3]

3.1.27

offgassing

evolution of gaseous products from a liquid or solid material into an atmosphere

Note 1 to entry: This is for the application in habitable volume considering medical impact on human health.

3.1.28

outgassing

evolution of gaseous species from a material, usually in a vacuum

3.1.29

particle

unit of solid or liquid matter with observable size

[SOURCE:ISO 14952-1:2003, 2.20]

3.1.30

particle concentration

<on surface> number of particles (3.1.29) per unit area

3.1.31

particle concentration

<by volume> number of particles (3.1.29) per unit volume of fluid

3.1.32

responsible organization

organization that is responsible for the contamination and cleanliness control programme (3.1.13) and which is provided with the authority and resources needed to carry out the programme

3.1.33

recovered mass loss

RML

Note 1 to entry: The quantity RML is introduced because water is not a critical contaminant (3.1.11) for some space systems (see 5.6.3). In most cases, the value of WVR is similar to that of the mass of outgassed water. However, WVR is not exactly the same as the water mass effused from the specimen. Therefore, RML is not equal to the real value of the mass loss other than water.

3.1.34

sensitive hardware

hardware that can be degraded by contamination

3.1.35

significant surface

surface of an item or product that is required to meet established cleanliness level (3.1.5) requirements

3.1.36

spacecraft charging

increase in electrostatic potential on spacecraft surfaces resulting from low-energy electron flux impinging on the surface

3.1.37

sterility

absence of viable microorganisms (3.1.23)

Note 1 to entry: Inactivated microbes can still represent an important form of biocontamination (3.1.3) .

3.1.38

supplier

provider

organization that provides a product or a service

Note 1 to entry: A provider can be internal or external to the organization.

Note 2 to entry: In a contractual situation, a provider is sometimes called “contractor”.

[SOURCE:ISO 9000:2015, 3.2.5, modified —"provider" has been changed to an admitted term.]

3.1.39

surface cleanliness

level of contamination on a significant surface (3.1.35)

3.1.40

total mass loss

TML

total mass of material outgassed from a test specimen that is maintained at a specified constant temperature and operating pressure for a specified time and measured within the test chamber

Note 1 to entry: TML is expressed as a percentage of the initial specimen mass.

3.1.41

visibly clean

absence of surface contamination when examined using a specified light source and angle of incidence, viewing distance and angle, and normal or magnified vision

Note 1 to entry: This level requires precision-cleaning methods but a particle (3.1.30) count may be optional.

Note 2 to entry: Fluorescence indicates possible contamination by, for example, a hydrocarbon.

Note 3 to entry: If recleaning fails to remove fluorescent indications, an investigation should be made to determine if the item material is naturally fluorescent or if the cleaning method is adequate.

[SOURCE:ISO 14952-1:2003, 2.35, modified — The abbreviated term"VC" has been removed.]

3.1.42

water vapour regained

WVR

mass of water vapour absorbed by a test specimen, after determination of total mass loss (TML) (3.1.40) and collected volatile condensable material (CVCM) (3.1.10) , on exposure to a specified relative humidity atmosphere (usually 50 % at 23 °C or 65 % at 20 °C) for 24 h

Note 1 to entry: Some types of materials continue to absorb water for longer than 24 h. Repeated mass measurements after various time periods (e.g. 24 h, 48 h and 72 h) give a better understanding of the material's water absorbency.