A membrane switch makes an excellent choice for humid or potentially wet environments – but only if the switch electronics are properly sealed.
Inadequate sealing of switch layers is a common cause of membrane switch failure. If the switch electronics are not properly sealed, moisture can penetrate the membrane switch and cause intermittent or complete switch failure. To prevent this, membrane switch layers should be sealed with heat under pressure.
Sealing a membrane switch is a manufacturing capability well outside of typical nameplate or graphic overlay companies. It is best to use a single-source supplier for your membrane switch electronics and your graphic overlay. This ensures you get a properly sealed interface.
Sealed membrane switches can be an economical solution for some product designs. Heat sealing adds processing time and material cost, but those up-front costs may be off-set by a reduction in product field failures. And a sealed membrane switch is likely a lower cost solution than rubber keypad or other ruggedized switching solution.
Manufacturers of sealed, custom membrane switches have engineering teams capable of evaluating your product switch needs and pricing parameters. And most offer this engineering service at no charge. Use their free design review service to determine if a sealed membrane switch would be a cost effective and reliable electronic interface for your product.