NASA Goddard Space Flight Center
Summary of Specification Language for Pure Tin
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Summary of the Current Pure Tin Prohibition for EEE Part Procurement Specifications (Military and NASA)

The table below includes a listing of EEE part procurement specifications (Military and NASA) that are commonly used for spaceflight part procurements.

The table provides:
Date of the most current specification revision
Brief explanation of the current "Pure Tin Prohibition Status" within the specification
Date and revision of the specification when the prohibition language was added (if at all)
Brief comments regarding the risk associated with the given specification
Based on the information provided, users can roughly determine the timeframe (lot date code) when the manufacturer was restricted from producing pure tin plated components.  However, the exact date when a given manufacturer’s product ceased to include pure tin has not been determined.

Notes:

1) The attachment does not cover ALL EEE part procurement specifications being used in spaceflight programs.  This list only encompasses the more commonly used specifications within NASA.  Numerous contractor-specific Source Control Drawings (SCD) are also in use which may or may not prohibit the use of pure tin plating.  Many of these SCDs are based upon the equivalent or similar military specification for that commodity.  The specific language in each SCD should be reviewed to determine if pure tin plating is restricted.
Relays
Connectors
Filters
Bus Wire

4) The complexity of some commodities such as connectors, wire and cable has made the completion of the table in those commodity sections difficult.  Updates to this table will be provided at a later date and will be made accessible on the Tin Whisker homepage.

This table will be updated to include additional information as it becomes available.
 (Last Updated 11/13/98)

Select the commodity type of interest
Capacitors Fuses Thermistors
Connectors Inductors Transformers
Crystals Microcircuits Wire and Cable
Discrete Semiconductors Relays  
Filters Resistors  

View a table that provides the actual specification language with respect to the use of pure tin

 Specification Number
Current Specification Revision Date
Summary of 
Current Pure Tin
Prohibition
Revision when Pure Tin Prohibition Language was Added
       
Capacitors
       
MIL-PRF-20
(Ceramic)
05/06/93
Rev H Am 2
Pure tin is allowed on terminals  
MIL-PRF-123
(Ceramic)
07/06/98
Rev B Am 5
Pure tin is allowed on chip capacitor terminations only  
MIL-PRF-23269
(Glass)
08/06/93
Rev E Am 1
 No pure tin allowed. Minimum of 3% lead.
08/06/93 
Rev E Am 1
MIL-PRF-39003
(Tantalum)
05/22/98
Rev H Am 4
No pure tin allowed. Minimum of 3% lead.
08/06/93
Rev H Am 2
MIL-PRF-39006
(Tantalum)
07/07/98
Rev E Am 1
No pure tin allowed on terminals. However, spec does not prevent tin plated cases.
12/24/93
Rev D Am 1
MIL-PRF-39014
(Ceramic)
09/16/97
Rev F
No pure tin allowed. Minimum of 3% lead.
11/23/93 
Rev E Am 4
MIL-PRF-49467
(Ceramic)
07/15/98
Rev A Am 2
No pure tin allowed. Minimum of 3% lead.
05/19/97 
Rev A
MIL-PRF-49470
(Ceramic)
07/15/98
Am 1
No pure tin allowed. Minimum of 3% lead.
11/19/97 
Base
MIL-PRF-55365
(Tantalum)
04/13/98
Rev D Am 1
No pure tin allowed. Minimum of 3% lead.
08/02/93 
Rev C Am 4
MIL-PRF-55681
(Ceramic)
06/29/98
Rev E Am 1
Pure tin is allowed.
07/13/94 
Rev D
MIL-PRF-83421
(Film)
12/30/93
Rev B Am 3
No pure tin allowed. Minimum of 3% lead.
07/04/93 
Rev B
MIL-PRF-87217
(Film)
02/23/94
Am 4
Pure tin is not expressly disallowed.  See MIL-PRF-83421.  
       
Connectors
       
MSFC 40M38277
 04/23/91 Pure tin finish is required for type NLS3H solder mount connectors only. Passivated stainless steel or nickel over aluminum is used on all other connectors.  All contacts are gold plated.  
MSFC 40M38298
 03/15/9 Pure tin is required for the shell of type NBS3H hermetic connectors and for the soldercups of type NBS0H and NBS3H hermetic connectors.  All other connectors are nickel coated.  Contacts and engagement surfaces of hermetic connector contacts are gold plated.  
MSFC 40M39569
 06/30/83 Pure tin is required for type NB3H solder mount connector shell only.  All other connectors are passivated stainless steel or nickel coated aluminum.  All contacts are gold plated.  
GSFC S-311-P-4
 09/05/91
Rev D
No pure tin allowed.  Connectors and contacts are gold plated.  
GSFC S-311-P-10
 09/21/92
Rev D
No pure tin allowed.  Connectors and contacts are gold plated.  
GSFC S-311-P-718
 9/05/91
Base Rev
No pure tin is used on connectors or contacts. Connector shells are nickel plated or chemically treated.  Contacts are gold plated.  
MIL-C-5015
 03/15/94
Rev G Am 5
No pure tin is used on connectors or contacts.  Soldercup contacts are pretinned with Sn60 tin-lead solder inside the solder well.  
MIL-PRF-24308
11/12/97
Rev D Am 2
Pure tin is required on Class H (Hermetic) shells and contact bodies.  Latest revision of MIL-PRF-23408/9 is not clear on material and finish for space.  Page 1 and 2 are in conflict. ;  Page 1 lists Class K while page 2 lists Class M non-magnetic.  Previous revision listed space grade to be Class K.  
MIL-C-26482
 01/03/91
Rev G Am 5
Pure tin is required for Series 1 and 2 hermetic seal connectors.  Series 1 solder type contacts are also pure tin plated.  
MIL-PRF-83513
04/22/97
Rev D
No pure tin is used.  Space grade connectors are coated with electroless nickel.  
MIL-PRF-39012
08/25/95
Rev D Am 1
No pure tin is used.  Beryllium copper connectors are gold plated.  Stainless steel connectors are passivated.  Contacts are gold plated on all surfaces.  
MIL-C-83517
07/07/98
Am 4
No pure tin is used.  Solder type contacts are gold plated.  Connector body is stainless steel.  Finish is passivated or gold plated.  Contact is gold plated.  
MIL-C-38999
 04/06/90
Rev J
Pure tin is required for Series I and II hermetic seal connectors only.  Solder contacts for hermetic connectors are gold plated.

The current unreleased Rev K draft includes a pure tin prohibition with 3% lead minimum. 

 
MIL-C-39029
 05/02/88
Rev E
No pure tin is allowed.  Solderless wrap termination areas and certain solder terminated contacts are pre-tinned with tin-lead alloy  
MIL-C-55302
 04/09/86
Rev E
No pure tin is allowed.  Solder contact termination end plating is tin-lead (50-70%) composition.  
MIL-C-85049
 08/30/90
Rev A
No pure tin is used.  
       
Crystals
       
MIL-O-55310
03/25/98
Rev D
 No pure tin allowed. Minimum of 3% lead.
03/15/94 
Rev C
       
Discrete Semiconductors (Diodes/Transistors)
       
MIL-S-19500
09/08/97
Rev K Am 1
No pure tin allowed. Minimum of 3% lead.
04/15/94 
Rev J
       
Filters
       
MIL-PRF-15733
11/15/96
Rev G Am 5
No pure tin allowed. Minimum of 3% lead.
12/31/93 
Rev G Am 4
MIL-PRF-28861
09/11/98
Rev B Am 4
No pure tin allowed. Minimum of 3% lead.
01/31/94 
Rev B
       
Fuses
       
MIL-PRF-23419
(Fuses)
06/12/98
Rev E Am 3
No pure tin allowed. Minimum of 3% lead.
06/01/94 
Rev E Am 1
MIL-PRF-39019
(Circuit Breakers)
08/27/97 
Rev D
No pure tin prohibition language.  
       
Inductors
       
MIL-C-39010
08/27/97
Rev E
No pure tin allowed. Minimum of 3% lead.
01/04/94 
Rev D
MIL-C-83446
10/03/94
Rev B Am 4
No pure tin allowed. Minimum of 3% lead.
10/03/94 
Rev B Am 4
MIL-STD-981
02/10/94 
Rev B
Solder is not allowed to be pure tin.  However, no min lead content is specified
02/10/94 
Rev B
       
Microcircuits
       
MIL-M-38510
08/27/93
Rev J Notice 1
No pure tin prohibition language.  
MIL-PRF-38534
09/12/96
Rev C Am 1
No pure tin allowed on terminations. Minimum of 2% lead.  No language about package plating restrictions
08/23/95 
Rev C
MIL-PRF-38535
12/01/97
Rev E
No pure tin allowed.
03/14/95 
Rev C
       
Relays
       
MIL-PRF-6106
12/01/97 
Rev K
No pure tin allowed. Minimum of 3% lead.
12/01/97 
Rev K
MIL-PRF-39016
06/30/98
Rev E Am 2
No pure tin allowed. Minimum of 3% lead.
07/18/94 
Rev E
MIL-PRF-83536
12/19/97
Rev A Am 1
No pure tin allowed. Minimum of 3% lead.
03/21/97 
Rev A
       
Resistors
       
GSFC S-311-P-672
04/06/98
Rev E
Information not available at time of table prep.  
GSFC S-311-P-683
07/02/96
Rev A
Information not available at time of table prep.  
GSFC S-311-P-742
12/26/95 
Rev C
Information not available at time of table prep.  
MIL-PRF-39005
(Wirewound)
03/16/98
Rev E Am 1
No pure tin allowed. Minimum of 3% lead.
07/01/93 
Rev D Am 2
MIL-PRF-39007
(Wirewound)
07/03/97
Rev H
No pure tin allowed. Minimum of 3% lead.
03/23/93 
Rev G Am 1
MIL-PRF-39008
(Carbon Comp)
04/11/97
Rev C Notice 1
Inactivated
No pure tin allowed. Minimum of 3% lead.
05/05/93 
Rev C Am 1
MIL-PRF-39009
(Wirewound)
07/03/97 
Rev D
A “Note” in Section 6 “prohibits” pure tin but does not specify a min lead content.  Terminals require minimum of 40% lead.
01/27/94 
Rev C Am 1
MIL-PRF-39015
(Variable)
06/09/98
Rev D Am 1
No pure tin allowed. Minimum of 3% lead.
04/27/93 
Rev C Am 2
MIL-PRF-39017
(Film)
05/19/97
Rev F
No pure tin allowed. Minimum of 3% lead.
07/01/93 
Rev E Am 2
MIL-PRF-55182
(Film)
09/17/98
Rev G Am 3
No pure tin allowed. Minimum of 3% lead.
08/11/93 
Rev F Am 2
MIL-PRF-55342
(Film)
09/17/98
Rev G Am 1
No pure tin allowed. Minimum of 3% lead.
05/10/93 
Rev E Am 2
MIL-PRF-83401
(Network)
03/18/96
Rev G
No pure tin allowed. Minimum of 3% lead.
06/11/93 
Rev F Am 3
MIL-PRF-914
(Network)
12/19/97
Rev A Am 1
No pure tin allowed. Minimum of 3% lead.  
       
Thermistors
       
MIL-T-23648
06/15/98
Rev D Am 1
No pure tin allowed. Minimum of 3% lead.
04/15/93 
Rev C Am 1
GSFC S-311-P-18
05/12/95
Rev G
No pure tin prohibition language.  
       
Transformers
       
MIL-T-27
06/06/94
Rev E Am 2
No prohibition in base spec.   
MIL-STD-981
02/10/94 
Rev B
Solder is not allowed to be pure tin.  However, no min lead content is specified.
02/10/94 
Rev B
       
Wire and Cable
       
S-311-P-13
06/07/96
Rev B
Pure tin is required for all wire

Pure tin coated wire is recommended for solder applications only.  Tin whisker growth is only a risk in areas where the insulation has been removed and the wire has not been coated with solder.

 
MIL-C-17
01/08/96
Rev G Am 3
Pure tin is required for the outer conductor of certain dash numbers of semi-rigid copper clad cable.  There is no impact on standard part numbers used by NASA.  
J-W-1177
10/16/96
Rev B Notice 1
Tin coating is not permitted.  The superseding document NEMA MW-1000 does not permit tin plating.  
MIL-W-22759
05/07/91
Rev E Am 1
Pure tin plating is allowed on some styles including (but not limited to) /16, /18, /32, /34.  
MIL-W-81381
09/08/87
Rev A Notice 1
Pure tin is required for detail specifications /21 and /22 only.

Pure tin coated wire is recommended for solder applications only.  Tin whisker growth is only a risk in areas where the insulation has been removed and the wire has not been coated with solder.

 
QQ-W-343
(Bus Wire)
04/18/97
Rev G
No pure tin prohibition language  
MIL-DTL-27500
12/10/97
Rev H
Pure tin is required for shield styles T, V, J and D  
 
Responsible NASA Officials:

   Michael Sampson/NASA GSFC Code 306
   Dr. Henning Leidecker/NASA GSFC Code 562		 Additional Researchers: 

   Jong Kadesch/Orbital Sciences Corp.
   Jay Brusse/QSS Group, Inc.

Last Updated:

April 20, 2005

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