Process Specification for Cleaning of Hardware

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| # Engineering Directorate                                             |
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| **Structural Engineering Division**                                   |
|                                                                       |
| **July 2008**                                                         |
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| ![](media/image1.png){width="1.3944444444444444in" height="1.15in"}   |
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| National Aeronautics and                                              |
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| Space Administration                                                  |
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| **Lyndon B. Johnson Space Center**                                    |
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| Houston, Texas                                                        |
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**Process Specification for Cleaning of Hardware**

####### Concurred by: \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_ David Lentz, Supervisor Date

Jacobs Sverdup Engineering

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| **Prepared by:** | ########                         |   |           |
+------------------+----------------------------------+---+-----------+
|                  | Erica S. Worthy, Materials       |   | Date      |
|                  | Engineer                         |   |           |
|                  |                                  |   |           |
|                  | Materials and Processes          |   |           |
|                  | Branch/ES4                       |   |           |
+------------------+----------------------------------+---+-----------+

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| **Approved by:** | ########                         |   |           |
+------------------+----------------------------------+---+-----------+
|                  | Brad Files, Chief                |   | Date      |
|                  |                                  |   |           |
|                  | Materials and Processes          |   |           |
|                  | Branch/ES4                       |   |           |
+------------------+----------------------------------+---+-----------+

  ----------- -------------------------------------------- ----------------
  REVISIONS                                                

  REVISION    DESCRIPTION                                  DATE

  \--         Original version                             5/96

  A           PRC was reviewed and updated for accuracy.   8/5/99
              Author was changed.                          

  B           Author change and replaced CFC-113 with      01/02/01
              HFE-7100 in Section 6.0                      

  C           General changes due to reorganization        2/20/04
              (changed EM to ES, MMPTD to SED,             
              Manufacturing, Materials, and Process        
              Technology to Structural Engineering. PRC    
              was updated and reviewed for accuracy.       

  D           Updated Organizational Changes and updated   1/30/06
              for accuracy.                                

  E           Clarified that TOC is required for water     7/10/2008
              cleanliness verification, major restructure  
              and check for accuracy.                      
  ----------- -------------------------------------------- ----------------

**1.0 [SCOPE]{.underline}**

This process specification establishes surface cleanliness requirements
for cleaning and packaging of JSC flight hardware and ground support
equipment (GSE).

**2.0 [APPLICABILITY]{.underline}**

This process specification applies to general cleaning of flight
hardware after fabrication (prior to assembly, after assembly, and/or
prior to delivery). It does not apply to in-process cleaning during
manufacturing (such as surface preparation for bonding or coating),
other than the descaling of stainless steel parts.

**3.0 [USAGE]{.underline}**

Cleanliness level requirements for particulate and nonvolatile residue
are defined in JPR 5322.1 "Contamination Control Requirements Manual."
The responsible design or use organization selects cleanliness levels
listed in Table I. GSE that interfaces with precision-cleaned flight
fluid systems shall be cleaned to at least the cleanliness level of the
flight hardware. Insufficient cleanliness of components used on oxygen
systems may result in the ignition of contamination or components.

Cleanliness levels shall be specified in a manner similar to the
following examples:

a.  Level 200 refers to limits on particulate matter contamination only.

b.  Level 200B refers to limits on particulate matter and non-volatile
    residue (NVR) contamination.

c.  Level B refers to limits on NVR only

d.  Level 200 A is a more stringent cleaning level than 300B for both
    particulate matter and NVR.

**[Note:]{.underline}** Contamination control in JSC flight hardware and
components used in oxygen services is imperative to prevent hazards and
component failure due to contamination**.**

This process specification shall be called out on the engineering
drawing by using a drawing note that identifies the process
specification to be used and the required level of cleanliness. For
example:

  -----------------------------------------------------------------------
  **AFTER HEAT TREATING, REMOVE OXIDE TINT BY DESCALING PER NASA/JSC
  PRC-5001.**

  -----------------------------------------------------------------------

  -----------------------------------------------------------------------
  **CLEAN ALL INTERNAL SURFACES TO LEVEL 300A PER NASA/JSC PRC-5001.**

  -----------------------------------------------------------------------

**4.0 [REFERENCES]{.underline}**

The following references were used to develop this process
specification:

##### ES-007.1 "Preparation and Revision of Process Specifications"

JSC 8500C "Engineering Drawing System Requirements"

The following documents are called out as an extension of the
requirements given in this specification. All documents listed are
assumed to be the current revision unless a specific revision is listed.

JPR 5322.1 "Contamination Control Requirements Manual"

ASTM A380-94a "Standard Practice for Cleaning, Descaling, and
Passivation of Stainless Steel Parts, Equipment, and Systems"

The latest revision of the documents listed below is applicable to the
extent specified herein.

**Refer any conflicts between the documents referred in this list to the
Materials and Processes Branch.**

### 4.1 FEDERAL STANDARDS AND SPECIFICATIONS

a.  FED-STD-102, \"Preservation, Packaging, and Packing Levels\"

b.  PPP-T-66, \"Type I, Class B - Tape: Pressure Sensitive Adhesive
    Water-Proof - for Packaging and Sealing\"

c.  TT-I-735, \"Specification, Isopropyl Alcohol\"

### 4.2 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION

a\. ISO-14644-1, "Clean rooms and Associated Controlled Environments
Part 1 Classification of Air Cleanliness"

b\. ISO-14644-2, "Clean rooms and Associated Controlled Environments
Part 2 Specifications for Testing and Monitoring to Prove Continued
Compliance with ISO-14644-1"

### 4.3 ASTM STANDARDS AND PRACTICES

a.  ASTM D2109-71, \"Nonvolatile Matter in Halogenated Organic Solvents
    and Their Admixtures\"

b.  ASTM F51-65T, \"Sizing and Counting Particulate Contamination in and
    on Clean Room Garments\"

c.  ASTM D1605, \"Standard Recommended Practices for Sampling
    Atmospheres for Analysis of Gases and Vapors\"

d.  ASTM D2407, \"Standard for Sampling Airborne Particulate
    Contamination in Clean Rooms for Handling Aerospace Fluids\"

e.  ASTM E21.05, \"Standard Method for Measurement of Nonvolatile
    Residue (NVR) on Surfaces\"

f.  ASTM E 595-20, \"Standard Test Method for Total Mass Loss and
    Collected Volatile Condensable Materials From Outgassing in a Vacuum
    Environment\"

g.  ASTM F24, \"Standard Method for Measuring and Counting Particulate
    Contamination on Surfaces\"

h\. ASTM G144 Standard Test for Determination of Residual Contamination
of Materials and Components by Total Carbon Analysis Using a High
Temperature Combustion Analyzer.

### 4.4 INSTITUTE OF ENVIRONMENTAL SCIENCES PUBLICATIONS

a.  \"IES Handbook of Recommended Practices, Contamination Control
    Division\"

b.  IES-CC-009-84, \"Compendium of Standards, Practices, Methods, and
    Similar Docu­ments Relating to Contamination Control\"

c.  IES-RP-CC-002-83-T, \"Laminar Flow Clean Air Devices\"

d\. IEST-STD-CC1246D, "Product Cleanliness Levels and Contamination
Control Program

### 4.5 MILITARY HANDBOOKS, SPECIFICATIONS, STANDARDS, AND TECHNICAL ORDERS (TOs)

a.  MIL-A-18455, \"Argon, Technical\"

b.  MIL-C-10578, \"Corrosion Removing and Metal Conditioning Compound
    (Phosphoric Acid Base)\"

c.  MIL-P-116, \"Preservation, Methods of\"

d.  MIL-P-27401, \"Nitrogen, Grade A, B, or C\"

e.  MIL-HDBK-406, \"Cleaning Materials for Precision-Cleaning and Use in
    Clean Rooms and Clean Work Stations\"

f.  MIL-HDBK-407, \"Precision-Cleaning Methods and Procedures\"

g.  MIL-HDBK-410, \"Contamination Control Technology, Logistic
    Protection of Precision-Cleaned Material\"

h.  MIL-M-9950, \"Military Specification: Missile Components; Liquid
    Oxygen, Liquid Nitrogen, Gaseous Oxygen, Gaseous Nitrogen,
    Instrument Air, Helium and Fuel Handling Systems; Cleaning and
    Packaging for Delivery\"

i.  MIL-STD-1695, \"Military Standard: Environment, Working, Minimum
    Standards\"

j.  TO 00-25-203, \"Contamination Control of Aerospace Facilities, US
    Air Force\"

k.  TO 42C-1-11, \"Cleaning and Inspection Procedures for Ballistic
    Missile Systems\"

### 4.6 NASA PROCEDURES, REQUIREMENTS, SPECIFICATIONS, AND STANDARDS

a.  JSC-01218, \"JSC Standard Procedures for Liquid and Gas Sampling\"

b.  JSCM 5341, \"Requirements for Sampling Atmospheric Gases and
    Hydrogen\"

c.  JSCM 8080, \"JSC Design and Procedural Standards Manual\"

d.  KSC-C-123, \"Specification for Surface Cleanliness of Fluid
    Systems\"

e.  MSCF-PROC-166D, \"Procedures for Cleaning, Testing, and Handling
    Hydraulic System Detailed Parts, Components, Assemblies, and
    Hydraulic Fluids for Space Vehicles\"

f.  MSFC-SPEC-164A, \"Specification for Cleanliness of Components for
    Use in Oxygen, Fuel, and Pneumatic Systems\"

g.  MSFC-STD-246, \"Standard Design and Operation Criteria of Controlled
    Environ­mental Areas\"

h.  NHB 53401, \"NASA Standard Procedures for the Microbiological
    Examination of Space Hardware\"

i.  NHB 5340.2, \"NASA Standards for Clean Rooms and Work Stations for
    the Microbially Controlled Environment\"

j.  NHB 8060.1C, \"Flammability, Odor, Offgassing, and Compatibility
    Requirements and Test Procedures for Materials in Environments That
    Support Combustion\"

k.  NSTS 07700, Volume XIV, \"Space Shuttle System Payload
    Accommodations,\" section 3.6.12, \"Contamination Control\"

l.  NSTS 08242, \"Limitations for Non-flight Materials and Equipment
    Used in and Around the Shuttle Orbiter Vehicles\"

m.  PRC-5002, "Process Specification for Passivation and Pickling of
    Metallic Materials"

n.  PRC-5010, "Process Specification for Pickling, Etching, and
    Descaling of Metals"

o.  SE-S-0073, \"NSTS Specification, Fluid Procurement and Use\"

p.  SN-C-0005, \"Contamination Control Requirements for the Space
    Shuttle Program\"

q.  SP-5015, \"Advances in Sterilization and Decontamination, A
    Survey,\" 1978

r.  SP-5076, \"Contamination Control Handbook,\" 1969

### 4.7 OTHER REFERENCES

a.  SAE-ARP-598, \"SAE Aerospace Recommended Practice for the
    Determination of Particulate Contamination in Liquids by the
    Particle Count Method\"

b.  ANSI Z9.2, \"Fundamentals Governing the Design and Operation of
    Local Exhaust Systems\"

c.  MDC H4070 (Space Station), \"Contamination Control Plan\"

d.  NFPA B93.19, \"Method for Extracting Fluid Samples from the Lines of
    an Operating Hydraulic Fluid Power System for Particulate
    Contamination Analysis\"

e.  NFPA 318, \"Standard for Fire Protection in Clean rooms\"

f.  Rockwell MA0110-301, \"Product Cleanliness\"

g.  SAE ARP-743, \"Procedures for the Determination of Particulate
    Contamination of Air in Dust Controlled Spaces by the Particle Count
    Method\"

h.  \"Spacecraft Cleanliness Control for Particles,\" 10th International
    Symposium on Contamination Control (ICCCS 90), Zurich, Switzerland,
    September 10-14, 1990

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5.  **[REQUIREMENTS]{.underline}**

All parts, components, assemblies, systems or related equipment
requiring cleaning must be cleaned to the specified cleanliness level
and inspected in accordance with this specification. Assemblies and
systems may require disassembly to permit cleaning. Remove any part or
component that might degrade during cleaning before cleaning and clean
as a separate item. Only trained and certified personnel must perform
cleaning and disassembly operations on precision cleaned parts.

**[NOTE:]{.underline}** It is the responsibility of the users of this
specification to review pertinent Materials Safety Data Sheets (MSDSs)
and materials specification to assure safety of the personnel,
protection of the environment and facilities in fulfilling the
requirements of this document.

**5.1 Cleaning**

All significant surfaces of the hardware must be pre-cleaned to remove
dirt, grit, scale, corrosion, grease, oil and other foreign matter prior
to any final precision cleaning process. Metallic parts shall be surface
treated (cleaned, passivated, pickled and/or coated) as necessary to
prevent latent corrosion and contamination.

Assembled items that do not lend themselves to this type of treatment
must be treated prior to assembly. Surface treated areas degraded during
subsequent fabrication and assembly shall be reprocessed as required to
restore the original protective finish.

The significant surfaces of pre-cleaned system hardware must be visibly
clean prior to precision cleaning. The precision cleaning levels are
specified JPR 5322.1 Table I. The precision cleaning operation must be
performed in an environmentally controlled area that meets the
cleanliness requirements of the parts to preclude adverse effects the
performance of the parts per JPR 5322.1. Precision cleaned hardware must
be packaged per JPR 5322.1 Table V prior to leaving the controlled
environment.

**5.2 Cleaning Fluid Requirements**

It is the cleaning contractor's responsibility to ensure that the
cleaning solution or cleaning process is compatible with any material or
part used in that solution or process.

The cleaning fluid(s) and cleaning procedure(s) used in a cleaning
method must be capable of assisting to clean the component, product,
etc., to the required cleanliness level. The cleaning methods and
procedures must be well understood. Additionally, the cleaning fluid
should be:

a\. Nontoxic (not harmful if inhaled or spilled on the skin) and
nonpoisonous.

b\. Non-explosive.

c\. Noncorrosive under normal use.

d\. Nonflammable.

**[NOTE:]{.underline}** (i) This does not limit potential cleaning
fluids only to nonflammable fluids. Flammable cleaning agents, such as
isopropanol, shall not be used when cleaning oxygen systems or equipment
that may combust flammable materials.

> \(ii\) In general, combustible cleaning agents must be used with care
> to clean systems or products that may combust the cleaning agent
> during cleaning; or even at a later time such as when the system or
> product is packaged, stored, used, etc.
>
> \(iii\) The cleaning contractor must verify complete solvent removal
> after final cleaning.

e\. Environmentally sound.

f\. Compatible with the system, product materials and hardware being
cleaned. Specifically, the cleaning fluid must not react with, combine
with, etch, or otherwise cause immediate or later degradation.

**5.3 New process approval**

For the introduction of new materials into pre-clean solvents or the
development of new processes that are not documented by existing
detailed process instructions (DPI), the Materials and Processes Branch
must be consulted regarding materials, cleaning processes and
compatibility concerns. Materials or sample parts that duplicate those
to be used in the new process must be tested to demonstrate
compatibility and to qualify the process. To obtain approval, the
contractor must submit a document JF881, with all of the following
information:

a\. Proposed cleanliness levels including analysis and rationale for the
selected cleanliness level.

> b\. Descriptions of items to be cleaned including identification of
> materials including trade names, specifications, chemical and physical
> properties and compatibility information.
>
> c\. Cleaning fluids information to include as applicable, trade names,
> specifications, chemical and physical properties, and compatibility
> information.

d\. Processing equipment and cleaning procedures to be used (e.g.
ultrasonic equipment, precision cleaning).

e\. Quality assurance provisions. This must include inspection(s) and
in-process control procedures to prevent contamination, latent
corrosion, or other degradation of surfaces and opened systems.

f\. Controlled environment levels to be maintained for cleaning and
handling.

g\. Preservation methods and materials.

h\. Verification methods.

Compatibility issues that must be considered and evaluated before
selecting a cleaning process are:

a\. Corrosion

b\. Embrittlement

c\. Leaching

d\. Residue

e\. Crazing (non-metallics)

f\. Reversion (non-metallics)

g\. Hydrolysis (non-metallics)

## **6.0 [SURFACE CLEANLINESS LEVELS]{.underline}**

Surface cleanliness levels are defined in Section 4.0 in JPR 5322.1
"Contamination Control Manual."

**[NOTE:]{.underline}** For ISS hardware, the ISS program requires a
cleanliness level of VC sensitive per SN-C-0005, as-specified in SSP
30426 "Space Station External Contamination Control Requirements" for
external hardware and in SSP 41000 "ISS System Specification" for
internal hardware.

### 6.1 PRECISION CLEANLINESS LEVELS

The responsible design or use organization shall specify the level of
cleanliness according to the cleanliness levels found in Table I.
Personnel trained in accordance with Section 9.0 of this manual shall
perform sampling and certification tasks to attain specified cleanliness
levels.

## **7.0 [CLEANING REQUIREMENTS]{.underline}**

The intent of this section is to specify those general requirements
applicable to cleaning processes. Pre-cleaning must be done prior to
final or precision cleaning.

Since the characteristics of the assemblies or components being cleaned
vary, this section does not describe all cleaning methods and processes.
The cleaning methods selected and used depend on which materials the
parts to be cleaned are fabricated from. Details of which solvents to
use for which materials can be found in DPI-5001-04 for pre-cleaning and
DPI-5001-07 for precision cleaning. However, some information about
nonmetallic pre-cleaning methods is covered separately in Section 7.4.3,
since these cleaning methods vary markedly from those used for metallic
components.

**7.1 PROCUREMENT**

The cleaning contractor shall adhere to the applicable contamination
control requirements of this specification and JPR 5322.1 "Contamination
Control Manual."

**7.2 ENVIRONMENTALLY CONTROLLED AREAS**

Precision cleaning, assembly, processing and functional testing of the
hardware shall be conducted in facilities which provide airborne
contamination levels compatible with the hardware cleanliness
requirements per JPR 5322.1 "Contamination Control Manual." Clean rooms
and other environmentally controlled areas (ECAs) shall be controlled by
approved documented procedures.

The cleaning contractor must establish and implement the requirements
for the periodic certifications of the clean room, clean workstations,
or other environmentally controlled areas. This certification process
shall be controlled by established and documented procedures. The Safety
and Mission Assurance Directorate has the approval authority for the
certification.

### 7.3 CLEANING FLUIDS AND SOLUTION CONTROL

#### 7.3.1 Cleaning Fluids

For all cleaning fluids, establish, document, and implement requirements
and procedures that control fluid composition, purity, cleanliness, and
use. Cleaning fluids selected for use in pre-cleaning solutions shall be
controlled by analysis, solution replacement, or adjustment to maintain
cleaning effectiveness and compatibility with the specific type of
material being cleaned.

#### 7.3.2 Solution Control Records

The cleaning contractor must maintain records indicating the scheduled
analysis, analysis results, and any solution replacement or adjustment
activities.

All fluids, equipment, and facilities used for cleaning to the VC or
VC + UV cleanliness levels shall be subject to the same minimum
requirements specified for pre-cleaning procedures. Cleaning with an
approved, compatible solvent (e.g., solvent wipe) is mandatory for VC
and VC + UV items, unless other methods are required by the hardware in
question. GC items do not require cleaning before inspection; cleaning
is required only if the item does not pass GC inspection. Use a GC
cleaning process compatible with the hardware materials.

*7.3.3 Aqueous Based Fluids*

a\. Aqueous based fluids must utilize reagent grade water. The reagent
water must meet the requirements of ASTM D1193, Type II except that
silica content is not required. Milli-Q water may be substituted for
reagent water.

b\. For passivation and picking baths, control chemistry per PRC-5002 or
PRC-5010.

*7.3.4 Final Rinsing Solvent*

Analyze final flush and verification fluids for precision cleanliness
for NVR prior to use to determine compliance with the stipulated
specification requirements.

> a\. Nonvolatile residue for HFE-7100 shall not be greater than 10
> milligrams per one liter as determined by SE-S-0073.

b\. If water is the final rinse fluid it must meet the requirements as
specified in SE-S-0073 Grade B.

c\. Isopropanol must meet the requirements of TT-I-735 filtered to 10
microns or better prior to use.

#### 7.3.5 Special Cleaning Processes

Control special cleaning processes, such as ultrasonic cleaning and
surge cleaning, by documented procedures.

7.3.5.1 [Ultrasonic Cleaning]{.underline}. Test ultrasonic cleaning
equipment to verify that adequate cavitation turbulence for good
cleaning action is maintained. Conduct such tests using the
manufacturer\'s recommended test method.

7.3.5.2 [Ultrasonic Fluid]{.underline}. The fluid used in ultrasonic
cleaning equipment should be as recommended by the manufacturer.
However, if an alternative fluid is used, perform tests to verify that
the alternative fluid does, indeed, perform the proper cleaning action
and is compatible with articles to be cleaned.

7.3.5.3 [Surge Cleaning]{.underline}. Subject surge or pressure and
vacuum cycle cleaning of components and systems to specific pressure or
flow controls to prevent damage to the item from pressure or vacuum. Do
not clean items such as pressure vessels, which are sensitive to
pressure cycle fatigue, using a surge cleaning procedure.

### 7.4 PRE-CLEANING HARDWARE

Pre-clean (rough clean) each item requiring precision cleaning to the VC
level before placing it in a clean room or clean workstation.
Pre-cleaning shall be controlled by detailed process instructions (DPI)
that have been approved by the NASA/JSC Materials and Processes Branch.
Nonmetallic materials shall be pre-cleaned with soap and water.

#### 7.4.1 Pre-cleaning Process Controls

Parts must be pre-cleaned to remove all visible contaminants without
removing or changing the characteristics of the base materials. All
traces of pre-cleaning materials shall be removed from parts at the
completion of the pre-cleaning process to prevent the future formation
of mineral salts and corrosion products. Use tests, such as pH testing,
to verify removal of all residuals.

#### 7.4.2 Work Flow

All steps in pre-cleaning procedures must progress in an uninterrupted
workflow through the final rinse and drying operation. If the workflow
is unavoidably interrupted, a recycling operation shall be specified in
the pre-cleaning procedure. Pre-cleaning procedures shall include, as a
minimum, protection of the item by interim packaging or other approved
means to prevent recontamination through all subsequent operations.

### 7.4.3 *Non-Metallic Cleaning and Rinse Test*

For the purpose of this document, nonmetallic materials include natural
rubber, Teflon^®^, nylon, Kel-F^®^, polytetrafluoroethylene,
polyethylene, polycarbonates, and other plastic or synthetic rubber
materials. The cleaning solution and method must not adversely affect
the materials or cause external damage, absorb the cleaning solution,
and/or cause outgassing. The Materials and Processes Branch must be
consulted when there are any compatibility concerns. When a final flush
is required for cleaning verification, perform it in accordance with
section 7.6.1, except that the solvent medium shall be high-purity
water.

### 7.5 INSPECTION

Accomplish non-UV visual inspection under a white light of sufficient
intensity to adequately illuminate the surface being inspected.
Inspections shall be performed as follows:

#### 7.5.1 Visual Inspection

[VC and VC + UV levels]{.underline}. Items must be inspected to the VC
level A visual inspection must be performed with the unaided eye
(corrective lenses are acceptable) under a white light of sufficient
intensity to illuminate the surface being inspected. Borescopes,
mirrors, or other devices may be used to increase accessibility during
inspection. Magnifying lenses may be used only to further identify
visible contaminants

Where configuration, color, or other item characteristics interfere with
visual observation, the following method shall be used to augment visual
inspections.

7.5.1.1 [Wipe Test.]{.underline} The surface to be inspected shall be
wiped with a lint-free, item-safe, and fluid-safe medium. The medium
shall be observed for the presence of contaminants. Care shall be taken
when wiping parts, especially since soft metals; e.g., aluminum can
abrade and soil the medium, giving an erroneous indication of
contamination. The wiping medium shall be subjected to the blacklight
inspection specified in section 7.5.2.

**[NOTE:]{.underline}** When the wiping medium is subjected to further
tests, such as blacklight or hydrocarbon evaluation, a baseline reading
of the blank medium must be determined and accounted for in subsequent
evaluations.

7.5.1.2 [Water Break Test]{.underline}. The surface to be inspected
shall be placed in the horizontal, face-upward position. Distilled
purified water from an atomizer shall be used to spray the surface to
completely cover the area of interest. The presence of droplets or
breaks in the water film will be an indication of possible oily
hydrocarbons.

#### 7.5.2 Blacklight (UV) Inspection

A visual observation of the part must be performed with the unaided eye
(corrective lenses are acceptable) under UV light (3,200 to 3,800
angstroms wavelength) for the presence of hydro­carbons. If the surface
to be inspected is inaccessible, a wipe test shall be performed and the
wiping medium inspected under UV light.

> **[NOTE:]{.underline}** Any contamination detected by the visual or
> blacklight inspection shall be cause for re-cleaning. If re-cleaning
> fails to remove fluorescent indications, investigate to determine if
> the item material is naturally fluorescent*.* Parts shall be inspected
> as specified in JPR 5322.1. For the GC Level, locations with cracks,
> crevices, holes, etc., which may trap or retain contamination, must
> receive particular attention.

*7.5.3 VC Standard, Sensitive, Highly Sensitive Levels.*

> Refer to Table A.2 of SN-C-0005 "Space Shuttle Contamination Control
> Requirements"

**[NOTE:]{.underline}** (1) JPR 5322.1 does not define the VC Standard,
Sensitive or Highly Sensitive levels; specify the minimum illumination
levels, or viewing distances. The hardware acceptance criteria are
essentially the same as in SN-C-0005.

\(2\) The viewing distance specified in SN-C-0005 is a result of its
heritage as a document for cleaning large surface areas such as the
Orbiter Payload Bay. Flight hardware at JSC is inspected at component
level and at a significantly closer distance typically one foot.

Per JPR 5322.1, visibly clean hardware must be cleaned prior to
inspection and generally clean hardware does not require cleaning unless
is fails inspection. Because the inspection requirements are much closer
than those specified in SN-C-0005, the lighting for the inspection is
adequate for all hardware verified to the JPR 5322.1 generally clean or
visibly clean level. This complies with the ISS requirements for visibly
clean sensitive per SN-C-0005.

### 7.6 PRECISION-CLEANING PROCESS CONTROLS

Hardware shall be precision-cleaned in a clean room environment,
following pre-cleaning operations described herein. Flush or wipe the
items to be precision-cleaned with a suitable cleaning solution or
solvent and/or vacuum clean or blow off with clean dry air to prevent
the entry of gross contaminants into the clean room environment.
Hardware must be precision cleaned using a precision-cleaning agent.

Work instructions that control the precision-cleaning processes shall be
developed by the cleaning organization and approved by the NASA/JSC
Materials and Processes Branch. At JSC, these work instructions are
called Detailed Process Instructions (DPI).

#### 7.6.1 Cleanliness Verification

Following precision cleaning, each item shall be rinsed with an
appropriate amount of unused precision-cleaning solvent usually (100 mL)
for each square foot of critical surface. Determine non-volatile residue
(NVR) in accordance with ASTM D2109-71, \"Nonvolatile Matter in
Halogenated Organic Solvents and Their Admixtures.\"

If high purity water is used as the final rinse solution for
verification, hydrocarbon content shall be determined using total
organic carbon (TOC) analyzing techniques per ASTM G144, "Standard Test
for Determination of Residual Contamination of Materials and Components
by Total Carbon Analysis Using a High Temperature Combustion Analyzer."

Particulate determination shall be made in accordance with the
requirements of SAE-ARP-598, \"SAE Aerospace Recommended Practice for
the Determination of Particulate Contamination in Liquids by the
Particle Count Method.\"

*7.6.2 GSE Interface Filtering*

For ISS hardware, GSE that interfaces with precision cleaned flight
fluid systems must incorporate filters as established and controlled by
SSP 30573 and located as close to the interface as possible where flow
could occur in to the flight hardware. This may also include outlet
lines if it is determined that some operations such as servicing and
describing fluids could permit flow in a reverse direction.

### 7.7 HANDLING

Refer to JSC 29253 "SR&QA Recommendation for Clean Room Gloves" for
gloves for wet and dry handling of hardware. Handle items cleaned to the
VC + UV, VC, and GC levels as follows:

a.  VC + UV level. Handle items cleaned to the VC + UV level the same as
    precision-cleaned items (i.e., with approved gloves, forceps, or
    tweezers).

b.  VC level. Handle items cleaned to the VC level with approved gloves
    if so specified by the responsible design or using organization.

c.  GC level. Gloves are not required for the handling of GC items.

**[NOTE:]{.underline}** For ISS, all hardware that has not been
precision cleaned shall not be brought into the vicinity of precision
cleaned hardware without the protecting the precision cleaned hardware

**7.8 DRYING**

Components must be thoroughly dried to remove residual cleaning,
rinsing, and/or verification media. Use nitrogen gas dry (MIL-P-27401,
Grade A, or equivalent). When purging is specified, the purging material
shall be a pre-cleaned, dry, inert gas (e.g., argon), conforming to
MIL-A-18455; or nitrogen, conforming to MIL-P-27401, Grade A, or
equivalent. Pre-filter gases to meet the cleanliness level of the item
being precision packaged.

**[NOTE:]{.underline}** It is the cleaning contractor's responsibility
to ensure removal of the above substances prior to packaging or placing
hardware into service.

### 7.9 FINAL PACKAGING

#### Package all cleaned and precision-cleaned items immediately after cleaning and drying in accordance to packing methods per JPR 5322.1 "Contamination Control Manual." To prevent galvanic corrosion, do not place metals dissimilar to the item in contact with the item. Do not use preservative materials on items, which have been precision-cleaned.

#### Prepackage electrical and electronic items that will require testing upon arrival at destination and during storage in a manner that will permit access to the leads, pigtails, etc., without degrading the integrity of the unit package. 

**[NOTE:]{.underline}** (1) Exercise caution when processing electrical
or electronic hardware that is sensitive to electrostatic discharge
(ESD) damage. Special materials and techniques may be necessary to
control ESD. Use materials used for both contamination and ESD control
only if approved by the Occupational Safety and Quality Assurance
Branch. Contamination control packaging shall not be placed inside
ESD-control packaging.

####  

### 7.10 CERTIFICATION DECALS 

Identify the bagged item with a decal containing identification,
inspection, and certification of cleanliness information. Decals
procured to meet the requirements of this section are not intended for
direct application to parts or equipment; therefore, the decals need not
be compatible with fuels or oxidizers. Apply decals to the outside of
the inner bag and over the ends of tape-sealed closures.

## **8.0 [STORAGE OF CLEANED ITEMS]{.underline}**

Remove completely cleaned and precision-cleaned and packaged items from
the clean room and place in an appropriate container or storage area to
protect the plastic bags and contents.

### 8.1 IDENTIFICATION AND CERTIFICATION

Cleaned items must be identified with the appropriate certification tags
and contain as a minimum the following information:

a\. Part of identification number

b\. Date of Cleaning

c\. Title, date and number of this standard or JPR 5322.1

d\. Service medium or intended use of component

e\. Acceptance stamps

f\. Cleanliness Level

**[NOTE:]{.underline}** The GC level does not require a cleanliness
certification decal, since protective packaging for contamination
control is not required.

Remove completely precision-cleaned and -packaged items from the clean
room and place in an appropriate container or storage area to protect
the plastic bags and contents.

### 8.2 ENVIRONMENTAL CONTROL

Store all precision-cleaned items in an enclosed, controlled area where
temperature and humidity are maintained within limits compatible with
the item and its packaging material. Filter the air supply through an
industrial-grade filter. Maintain the enclosed area in a manner
consistent with good housekeeping practices. Establish and document
periodic cleaning schedules.

### 8.3 INSPECTION

Inspect stored precision-cleaned items periodically, at least once every
2 years, for the integrity of the outer bag and, on a sample basis, for
corrosion or other degradation of the packaged item. To inspect, remove
the outer bag and visually inspect the item through the inner wrap. Any
discoloration, visible contamination, etc., shall be cause for rejection
and re-cleaning of the lot sampled. If no cause for rejection is found,
apply a new outer bag and reseal in the normal manner.

###  ACCESS CONTROLS

Establish adequate controls and procedures to limit access to storage
areas for precision-cleaned items to personnel specifically trained in
the handling of precision-cleaned items. At JSC, all hardware is treated
as flight hardware.

## **9.0 [PERSONNEL TRAINING]{.underline}**

This section defines the minimum training requirements for operational,
technical, and management personnel. The cleaning organization must
train all personnel training in ECA operations as required and shall be
accomplished by the successful completion of a formal training program
per JPR 5322.1. In addition to ECA disciplines, personnel need only be
trained and qualified in the operations that encompass their particular
job responsibilities.

A certification training course shall be established and required for
personnel working with precision-cleaned hardware for the ISS program
regardless of work site according to ISS-PI-002 Maintenance of Fluid
Systems Cleanliness.

Retraining of all personnel must be performed as required. Training
records and certifications must be kept with traceable documentation.

**[NOTE:]{.underline}** Personnel requiring entry to the ECA on a visit
or on a temporary basis must be knowledgeable in the basic ECA
disciplines or shall be instructed before entering. An escort qualified
for ECA entry must escort and be directly responsible for such
personnel. The appropriate ECA supervisor controls entry of visitors or
temporary personnel to prevent overpopulation and compromise of ECA
integrity.

**10.0 [DEFINITIONS]{.underline}**

Cleanliness Level (1) An established maximum of allowable contaminants
based on size, distribution, or quantity on a given area or in a
specific volume or (2) absence of particulate and nonparticulate matter
visible under white light and/or UV illumination

Contaminant Any unwanted matter that could be detrimental to the
required operation, reliability, or performance of a part, component,
subsystem, or system

Environmentally Controlled Area A classification which includes clean
rooms, laminar flow clean work stations, and CWAs

Generally Clean (GC) Free of manufacturing residue, dirt, oil, grease,
processing debris or other extraneous contamination. This level is
achieved by washing, wiping, blowing, vacuuming, brushing or rinsing

Micron A unit of measurement equal to one-millionth of a meter or
approximately 0.00003937 in. (e.g.,\
25 microns are approximately 0.001 in.)

Nonparticulate Matter Matter (usually film) with no definite dimension

Nonvolatile Residue (NVR) Soluble (or suspended) material and insoluble
particulate matter remaining after controlled evaporation of a filtered
volatile solvent usually measured in milligrams. Filtration is normally
through a 0.45-micrometer or 0.8-micrometer membrane filter before
evaporation

Particulate Matter The general term applied to matter with observable
length, width, and thickness (as contrasted to nonparticulate film
matter without definite dimensions)

Precision-cleaning Final or fine cleaning accomplished in a controlled
environment to achieve precision cleanliness. Surface cleaning with an
approved, compatible solvent (e.g., solvent wipe) is satisfactory for
VC + UV and VC items

Precision Cleanliness A degree of cleanliness which requires special
equipment and techniques for determination; precision cleanliness levels
normally include limits for particulate sizes and quantities

Precision-Clean Packaging Packaging or protection used to preserve
precision cleanliness for a specific period and condition

Purge To flow a gas through a system (or pipeline, tube, tank, etc.) for
the purpose of removing residual fluid or for providing a positive flow
of gas from some opening in the system

Silting Accumulation of minute particles in the size range normally not
counted with the respective service medium

Total Organic Carbon (TOC) Amount of carbon molecules in a sampling
fluid, typically water, as measured by controlled combustion. TOC is
reported in parts per million (ppm) by weight as carbon

Visibly Clean (VC) Free of all particulate and nonparticulate matter
visible to the unaided eye (corrective lenses are acceptable)

Visibly Clean + Ultraviolet (VC + UV) Visibly clean (as defined above)
and without fluores­cent matter detectable with a UV light (black light)
of 3,200 to 3,800 angstroms wavelength

Visual Cleanliness Levels A category which includes VC, VC + UV, and GC
cleanliness levels

**Table I. Classification of Cleanliness Levels Requirements**

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