ASTM F2072-01(2007)

Standard Practice for Hosedown of a Membrane Switch

SIGNIFICANCE AND USE
The presence of water inside a membrane switch can affect its mechanical operation or electrical functionality, or both.
This practice establishes a procedure to verify the ability of a membrane switch to resist the entry of liquid into itself or a finished product, or both. It is useful in identifying design deficiencies.
Hosedown testing may be destructive, therefore any samples tested should be considered unfit for future use.
SCOPE
1.1 This practice establishes procedures for the hosedown of a membrane switch to verify adequate protection from ingress of water from a high-volume water spray.
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 NEMA Publication Number 250-1991 Section 6.7 which is a test for hosedown of a finished product housing.

General Information

• Status: Historical
• Publication Date: 31-Jan-2007
• ICS: 31.220.20 - Switches
• Technical Committee: F01 - Electronics
• Drafting Committee: F01.18 - Printed Electronics

Relations

• Replaces: ASTM F2072-01 - Standard Practice for Hosedown of a Membrane Switch
• Effective Date: 01-Feb-2007

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: F2072 − 01 (Reapproved 2007)
StandardPractice for
Hosedown of a Membrane Switch
This standard is issued under the fixed designation F2072; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 5. Interferences
1.1 Thispracticeestablishesproceduresforthehosedownof 5.1 External Venting—Any deliberate external venting of
a membrane switch to verify adequate protection from ingress the switch will allow liquid to enter.
of water from a high-volume water spray.
5.2 Atmospheric Pressure—Significant changes in atmo-
1.2 This practice can also be used to verify the ability of a spheric pressure during the test or at different facilities may
membrane switch or graphics layer to act as a liquid seal for a alter the time in which leakage might occur.
finished product.
5.3 Duration of Test—Longer exposure time increases the
1.3 Additional test methods or practices can be incorporated possibility of leakage.
to investigate specific results or capabilities.
5.4 Dye Coloring—Choose a dye coloring that will not
1.4 This practice is a modification of NEMA Publication chemically attack the materials.
Number 250-1991 Section 6.7 which is a test for hosedown of
6. Apparatus
a finished product housing.
6.1 Water Supply, capable of delivering a stream of water at
2. Referenced Documents
a rate of at least 65 gal/min through a 1 in. (25 mm) internal
2.1 NEMA Publication 250-1991
diameter nozzle for the specified duration,
6.2 An appropriate device or fixture to hold the switch in a
3. Terminology
fixed position,
3.1 Definitions:
6.3 Any additional equipment as required by other test
3.1.1 membrane switch, n—a momentary switching device
methods employed, and
in which at least one contact is on, or made of, a flexible
substrate.
6.4 Nozzle with 1 in. (25 mm) internal diameter.
3.1.2 specified resistance, n—maximum allowable resis-
7. Test Specimen
tance as measured between two terminations whose internal
switch contacts, when held closed, complete a circuit. 7.1 The test specimen will be a membrane switch with or
without graphics laminated to a rigid material or the final
4. Significance and Use
intended mounting configuration (using a clear material will
4.1 The presence of water inside a membrane switch can facilitate visual inspection).
affect its mechanical operation or electrical functionality, or
8. Conditioning
both.
8.1 Condition specimens by exposure to ambient conditions
4.2 This practice establishes a procedure to verify the ability
for 72 h prior to hosedown to allow full cure of adhesives.
of a membrane switch to resist the entry of liquid into itself or
a finished
...