The presence of water inside a membrane switch can affect its mechanical operation or electrical functionality, or both. Electrical failure can result as short circuits due to silver migration or exceeding the specified resistance due to oxidation.

This practice establishes a procedure to verify the ability of a membrane switch to resist the entry of liquid in itself or a finished product, or both. It is useful in identifying design deficiencies.

Submersion testing may be destructive, therefore any samples tested should be considered unfit for future use.

1.1 This practice establishes procedures for the submerging of a membrane switch to verify resistance 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 stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.