ASTM F1895-98

Practice for Submersion of a Membrane Switch

SCOPE
1.1 This practice establishes procedures for the submerging of a membrane switch to verify resistant to ingress of a specified liquid.  
1.2 This practice can also be used to verify the ability of a membrane switch or graphics layer to act as a liquid seal for a finished product.  
1.3 Additional test methods or practices can be incorporated to investigate specific results or capabilities.  
1.4 This practice is a modification of National Electrical Manufacturers Assoc. (NEMA) Publication Number 250-1991 Section 6.10, which is a test for submersion of a finished product housing.  
1.5 The values states in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

General Information

• Status: Historical
• Publication Date: 09-May-1998
• ICS: 31.220.20 - Switches
• Technical Committee: F01 - Electronics
• Drafting Committee: F01.18 - Printed Electronics

Relations

• Replaced By: ASTM F1895-98(2004) - Practice for Submersion of a Membrane Switch
• Effective Date: 01-May-2004

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F 1895 – 98
Practice for
Submersion of a Membrane Switch
This standard is issued under the fixed designation F 1895; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 4.2 This practice establishes a procedure to verify the ability
of a membrane switch to resist the entry of liquid in itself or a
1.1 This practice establishes procedures for the submerging
finished product, or both. It is useful in identifying design
of a membrane switch to verify resistance to ingress of a
deficiencies.
specified liquid.
4.3 Submersion testing may be destructive, therefore any
1.2 This practice can also be used to verify the ability of a
samples tested should be considered unfit for future use.
membrane switch or graphics layer to act as a liquid seal for a
finished product.
5. Interferences
1.3 Additional test methods or practices can be incorporated
5.1 External Venting—any deliberate external venting of the
to investigate specific results or capabilities.
switch will allow liquid to enter.
1.4 This practice is a modification of National Electrical
5.2 Atmospheric Pressure—significant changes in atmo-
Manufacturers Assoc. (NEMA) Publication Number 250-1991
spheric pressure during the test or at different facilities may
Section 6.10, which is a test for submersion of a finished
alter the time in which leakage might occur.
product housing.
5.3 Duration of Test—longer submersion time increases the
1.5 The values stated in inch-pound units are to be regarded
possibility of leakage.
as the standard. The values given in parentheses are for
5.4 Dye Coloring—chose a dye coloring that will not
information only.
chemical attack the materials.
2. Referenced Documents
6. Apparatus
2.1 National Electrical Manufacturers Assoc.:
2 6.1 Tub of sufficient size and depth (w/cover) for the entire
NEMA Publication 250-1991
switch, including any mounting surface to be submerged by at
3. Terminology least 1 in. (25.4 mm) or as specified.
6.2 An appropriate device of fixture to hold the switch in a
3.1 Definitions:
fixed position.
3.1.1 membrane switch—A momentary switching device in
6.3 Any additional equipment as required by other test
which at least one contact is on, or made of, a flexible
methods employed.
substrate.
3.1.2 specified resistance—maximum allowable resistance
7. Test Specimen
as measured between two terminations whose internal switch
7.1 The test specimens may be membrane switches with or
contacts, when held closed, complete a circuit.
without graphics.
3.1.3 silver migration—growth of fine crystals between
7.2 Laminate to specified material or to a rigid clear
silver conductors of a thick film circuit due to an ionic reaction
material (using a clear material will facilitate visual inspec-
to the presence of water and an applied dc voltage potential.
tion).
4. Significance and Use 7.3 Membrane switches or graphic overlays designed to act
as a liquid seal for the finish
...