Although in ASCII, here are the requirements for J-STD-001
Hope this helps.
Regards
Dave Bergman, IPC
8.0 CLEANLINESS REQUIREMENTS
When the post soldering cleanliness designator (see 8.3.2.1) specifies cleaning option C-O (no surfaces to be cleaned), the soldered assemblies must meet the visual inspection requirements of 8.2.1 except that evidence of flux residue is permitted. If cl
eaning is required (per 8.3) during and after processing, parts, subassemblies, and final assemblies shall be cleaned within a time frame that permits appropriate removal of contaminants (especially flux residue).
All items cleaned must be cleaned in a manner that will prevent detrimental thermal shock and intrusion of cleaning media into components that are not totally sealed. The items cleaned shall be capable of meeting the cleanliness requirement as specified
herein.
8.1 Cleaning Process Requirements
8.1.1 Compatibility
The cleaning media and equipment shall be selected or their ability to remove both ionic and non-ionic contamination and shall not degrade the materials, markings, or parts being cleaned. Analysis and documentation demonstrating compliance with these re
quirements shall be available for review.
8.1.2 Pre-soldering Cleanliness Requirements
The cleanliness of terminals, component leads, conductors, and printed wiring surfaces shall be sufficient to ensure solderability (see 5.2). For post-soldering cleaning option C-O (no surfaces to be cleaned), their cleanliness must be sufficient to en
sure compliance with the final assembly cleanliness requirements (see 8.3.4).
8.1.3 Post-soldering Cleaning
When cleaning is required, flux residue shall be removed as soon as possible, preferably within one hour after soldering. Some fluxes or processes may require more immediate action to facilitate adequate removal. Mechanical means such as agitation, spray
ing, brushing, etc., or vapor degreasing and other methods of application may be used in conjunction with the cleaning medium. The time between soldering and completion of cleaning may be extended for hand soldering operations provided interim cleaning is
performed and complete cleaning is performed prior to the end of the production shift.
Note: Terminations internal to self-sealing devices (e.g., heat shrinkable solder devices) per MIL-S-83519 shall be exempt from the cleaning requirements of this standard when the device encapsulates the solder connection.
8.1.3.1 Ultrasonic Cleaning
Ultrasonic cleaning is permissible:
a. on bare boards or assemblies, provided only terminals or connectors without internal electronics are present, or
b.on electronic assemblies with electrical components, provided the contractor has documentation available for review showing that the use of ultrasonics does not damage the mechanical or electrical performance of the product or components being cleaned.
8.2 Cleanliness Verification
Assemblies shall meet the requirements of 8.3 for cleanliness. The following methods are to be used to assess the amount of remaining particulate or foreign matter and both flux residues and other ionic or organic contaminants.
8.2.1 Visual Inspection
Visual inspection shall be used to assess the presence of foreign particulate matter as required in Section 8.3.1, or flux and other ionic or inorganic residues as required in Section 8.3.2. When done as part of a documented process control and product im
provement system, visual inspection shall be based on a statistical sample (see 12.1.3). Otherwise, one hundred percent visual inspection shall be performed.
8.2.2 Testing
Periodic testing of cleanliness of the assembly after final cleaning (e.g., the cleaning prior to conformal coating, encapsulation, or incorporation into the next higher assembly) shall be conducted on a random sample basis (see 12.1.3) to ensure the ade
quacy of the cleaning process(es), as required in 8.3.4. If any assembly fails, the entire lot shall be re-cleaned and a random sample of this lot and each lot cleaned since performing the last acceptable cleanliness test shall be tested. The frequency o
f testing shall be a minimum of once each eight hour shift unless the process control system data supports a change in frequency.
8.3 Post-solder cleanliness
Cleaning of assemblies shall be performed as necessary to remove (1) particulate matter as required in 8.3.1 and (2) flux residues and other ionic or organic contaminants as required in 8.3.2.
8.3.1 Particulate Matter
Assemblies shall be free of dirt, lint, solder splash, dross, etc. Solder balls must neither be loose nor violate minimum electrical design clearance.
8.3.2 Flux Residues and Other Ionic or Organic Contaminants
It is the responsibility of the user to specify a cleanliness designator that establishes the cleaning option and test for cleanliness in accordance with
8.3.2.1. The user and manufacturer shall agree to the cleaning requirements and the tests for cleanliness indicated by the cleanliness designator. In the absence of a specified cleanliness designator, the designator C-22 as described in the following para
graphs must apply. In addition, the visual requirements for cleanliness (per 8.3.2.2) shall be specified.
8.3.2.1 Post-soldering Cleanliness Designator
The cleanliness designator shall be in the following form:
A 2-digit (minimum) code describes the cleanliness requirements for all assemblies covered under this standard. This code begins with the letter ``C'' then a dash followed by two or more digits. The first digit represents the cleaning option described in
8.3.3 and the second and following digits indicate the requirements for cleanliness testing described in 8.3.4.
8.3.2.2 Visual Requirements
Surfaces cleaned should be inspected without magnification and shall be free of visual evidence of residue or contaminants. Surfaces not cleaned may have evidence of flux residues.
8.3.3 Cleaning Option
The first digit of the cleanliness designator defines the cleaning option. The following digits are used to define the surfaces of the assembly that are to be cleaned:
m0 = No surfaces to be cleaned
m1 = One side (wave solder source side) of assembly to be cleaned
m2 = Both sides of assembly to be cleaned
8.3.4 Test for Cleanliness
The second and following digits of the cleanliness designator define the requirements for cleanliness testing. The following digits are to be used:
m0 No test for cleanliness required
m1 Test for rosin residues required (8.3.5)
m2 Test for ionic residues required (8.3.6and/or8.3.7)
m3 Test for surface insulation resistance (8.3.8)
m4 Test for other surface organic contaminants (8.3.9)
m5 Other tests as defined by user/manufacturer agreement
8.3.5 Rosin Residues
Assemblies shall be tested in accordance with IPC-TM-650, Test Method 2.3.27 and shall comply with the following requirements for the maximum allowable level of rosin flux residues:
Class 1 assemblies less than 200<mu>g/cm<sup>2
Class 2 assemblies less than 100<mu>g/cm<sup>2
Class 3 assemblies less than 40<mu>g/cm<sup>2
8.3.6 Ionic Residues (Instrument Method)
Assemblies shall be tested in accordance with IPC-TM-650, Test Method 2.3.26, (Ionizable Detection of Surface Contaminants [Dynamic Method]), or 2.3.26.1 (Ionizable Detection of Surface Contaminants [Static Method]) and shall contain less than 1.56 micro
gram/cm<sup>2 sodium chloride (NaCl) equivalent ionic or ionizable flux residue. Other methods may be used when the sensitivity of the alternative method is shown to be equal to or better than the above methods with respect to detecting ionizable surface
contamination.
Note: In comparing the sensitivity between methods, the solvent used to extract the residue, the method used to present the solvent to the assembly and the method of detecting the residue should all be considered.
8.3.7 Ionic Residues (Manual Method)
Assemblies shall be tested in accordance with Appendix G or IPC-TM-650, Test Method 2.3.25, Resistivity of Solvent Extract. The surface contamination shall be less then 1.56 mu>g/cm<sup>2 NaCl equivalent ionic or ionizable flux residue.
Other acceptance values may be specified by the user for equivalent tests.
8.3.8 Surface Insulation Resistance (SIR)
IPC-B-36 test specimens or equivalent assembly circuitry processed in the same manner as the assemblies being produced shall be tested for the effect of the contamination on the electrical insulation resistance of printed boards under high temperature and
humidity in accordance with IPC-TM-650, Test Method 2.6.3.3. The test specimens shall have a minimum resistance of 100 megohms after soldering and/or cleaning. The user and manufacturer may agree upon other test specimens, test conditions, and/or SIR re
quirements.
8.3.9 Other Contamination
Assemblies tested in accordance with IPC-TM-650, Test Method 2.3.38, Surface Organic Contaminant Detection Test (In-House Method) shall not exceed the maximum acceptance level established by mutual agreement between user and manufacturer.
On Wed, 19 Mar 1997, Wasan Singhatong wrote:
> Do anybody know which IPC's spec. specied the allowable ionic contam. on
> the PWA. Or any other standard.
>
> Wasan S.
> Rel Eng.
> "[log in to unmask]"
>
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